Is there any other way to remove camshaft sprocket on '95 mercury mystique besides buying a special tool ?

There are no timing marks on this engine - the engine has to be "locked" using special engine locking / setting kit which you wil have to obtain to do the job.

I will give you the instructions to do the job for when you have the locking kit to do the job.. as follows:

Removal

1. Raise and support front of vehicle.
2. Remove:
   • • RH front wheel.
     • RH inner wing panel.
     • Air filter assembly.
3. Support engine.
4. Remove:
   • • RH engine mounting and bracket.
     • Timing belt upper cover,
     • AC receiver/drier (if fitted). DO NOT disconnect hoses.
     • Timing belt lower cover.
     • Auxiliary drive belt.
     • Support bracket between gearbox and cylinder block (Palio).
5. Palio: Remove bell housing cover plate. Fit flywheel locking tool. Tool No.1.867.029.000. or equivalent commercially available.
6. Remove:
   • • Crankshaft pulley bolts
     • Crankshaft pulley
     • Spark plug leads.
     • Ignition coil and bracket.
     • Spark plugs.
7. Fit dial gauge and adapter to No.1 cylinder. Tool No.1.860.895.000.
8. Turn crankshaft to TDC on No.1 cylinder. Set dial gauge to zero.
9. Ensure notch in rear of camshaft aligned as shown.
10. Install camshaft aligning tool. Tool No.1.870.823.000
11. 
    NOTE: If camshaft aligning tool cannot be fitted: Turn crankshaft one turn clockwise.

Installation

1. Ensure No.1 cylinder at TDC by turning crankshaft slightly clockwise and anti-clockwise. Use dial gauge .
2. Ensure camshaft aligning tool fitted correctly
3. Hold camshaft sprocket. Use tool No.1.860.831.000/001
4. Slacken camshaft sprocket bolt
5. Fit timing belt in following order:
   • • Crankshaft sprocket.
     • Water pump sprocket.
     • Camshaft sprocket.
     • Tensioner pulley.
   NOTE: Observe direction of rotation marks on belt.
6. Fit tensioning tool locating pegs to tensioner pulley holes -Tool No.1.860.745.100/300. Ensure tensioning tool arm is horizontal.
7. Set weight at 70 mm mark on scale bar.
8. Hold camshaft sprocket
9. Tighten camshaft sprocket bolt - Tightening torque: 70 Nm.
10. Remove aligning tool
11. Turn crankshaft two turns clockwise.
12. Ensure No.1 cylinder at TDC by turning crankshaft slightly clockwise and anti-clockwise. Use dial gauge
13. Ensure camshaft aligning tool can be fitted - If not: Repeat installation procedure.
14. Tighten tensioner nut to 28 Nm
15. Remove:
    • • Tensioning tool
      • Camshaft aligning tool
      • Dial gauge
16. Install components in reverse order of removal.
17. Tighten crankshaft pulley bolts - Tightening torque: 20 Nm + 90°.

Im not positive but I think it is backward threaded you have to turn it clockwise.

yes maybe you need a spanner tool MB990775, or something similar.

YOU HAVE TO REMOVE TIMING BELT.NOT A HARD JOB BUT YOU NEED A REPAIR MANUAL TO LOOK AT TIMING BELT TIMING MARKS LOCATION ON CAMSHAFTS CHAIN SPROCKETS AND CRANKSHAFT GEAR TIMING MARKS.

Timing Belt and Sprockets REMOVAL & INSTALLATION Fig. 1: If you plan on reusing the timing belt, make sure you note the direction of the rotation before removal Fig. 2: If the special tool is unavailable, a suitable length and width straight edge can be used to align the camshafts Fig. 3: Camshaft alignment using the special service tool Fig. 4: Insert the crankshaft damper bolt to turn the crankshaft and . . . Fig. 5: . . . align the camshafts and the . . . Fig. 6: . . . crankshaft before removing the old belt Fig. 7: Loosen the timing belt tensioner pulley bolt, slide the tensioner back and . . . Fig. 8: . . . tighten the bolt to the farthest right hand side as possible to hold the release the tensioner pulley so that the belt can be removed Fig. 9: . . . remove the belt starting from around the camshaft pulleys Fig. 10: Installation of the tensioner spring and retaining bolt For information on timing belt recommended replacement interval, refer to Section 1. CAUTION
The 2.0L engine is an interference motor. Extending the replacement interval could lead to the belt breaking and severe and costly engine damage. Care must be taken if rotating the crankshaft or camshafts with the belt off, if resistance is felt, do not force them to turn.

1. Disconnect the negative battery cable.
2. Remove the timing belt covers as outlined in this Section.
3. Remove the valve cover.
4. Place Camshaft Alignment Timing Tool T94P-6256-CH or equivalent, into the slots of both camshafts at the rear of the cylinder head to lock the camshafts into position. NOTE: If the special tool is unavailable, a suitable length and width straight edge can be used to align the camshafts.
   
5. Loosen the camshaft timing belt tensioner pulley retaining bolt and move the tensioner pulley to relieve the tension on the timing belt.
6. Temporarily tighten the tensioner in this position. NOTE: If the timing belt is to be reused, mark the belt for the direction of rotation before removing to prevent premature wear or failure.
   
7. Remove the timing belt.
8. If required, remove the sprockets as follows:
   1. Hold the camshaft with an appropriate camshaft sprocket holding tool.
   2. Loosen and remove the camshaft sprocket retaining bolt.
   3. Remove the sprocket from the camshaft.
   4. Repeat the procedure for the 2nd camshaft sprocket.
   5. Remove the crankshaft sprocket.
9. Slide the crankshaft sprocket onto the crankshaft aligning the key-way.
10. Align the camshafts using the Camshaft Alignment Timing Tool T94P-6256-CH. NOTE: If the special tool is unavailable, a suitable length and width straight edge can be used to align the camshafts.
    
11. Reinstall the sprockets onto the camshafts and loosely install the camshaft retaining bolts.
12. Tighten the camshaft sprocket retaining bolts to 47–53 ft. lbs. (64–72 Nm) .
13. Loosely install the crankshaft pulley to verify that the engine is at TDC. Realign the marks if they have moved.
14. Verify that the camshafts are aligned. NOTE: It is recommended to purchase a tensioner spring and retaining bolt through the dealer parts to apply the proper tension for used or new belt installations. The spring is bolted to the tensioner assembly and becomes a part of the engine. Ignore this notice if the tensioner spring is already installed.
    
15. Reinstall the retaining bolt (W700001-S309) into the hole provided in the cylinder block and place the tensioner spring (6L277) between the bolt and the camshaft timing belt tensioner pulley.
16. Tighten the retainer bolt to 71–97 inch lbs. (8–11 Nm) .
17. Remove the crankshaft pulley and install the timing belt onto the crankshaft sprocket, then onto the camshaft sprockets working in a counterclockwise direction.
18. Tighten the camshaft sprocket retaining bolts to 47–53 ft. lbs. (64–72 Nm) .
19. Be sure that the span of the camshaft timing belt between the crankshaft sprocket and the exhaust camshaft sprocket is not loose.
20. Be sure that the camshaft timing belt is securely aligned on all sprockets.
21. Reinstall the lower timing belt cover and tighten the retaining bolts to 53–71 inch lbs. (6–8 Nm) .
22. Apply silicone sealer to the key-way of the crankshaft pulley and install. Tighten the retaining bolt to 81–89 ft. lbs. (110–120 Nm) .
23. Inspect the timing mark on the crankshaft pulley to verify that the engine is still at TDC.
24. Loosen the camshaft timing belt tensioner pulley retaining bolt and allow the tensioner spring attached to the pulley to draw the tensioner pulley against the camshaft timing belt.
25. Remove the camshaft alignment timing tool from the camshafts at the rear of the engine.
26. Turn the crankshaft two revolutions in a clockwise direction.
27. Tighten the camshaft timing belt tensioner pulley retaining bolt to 26–30 ft. lbs. (35–40 Nm) .
28. Recheck that the crankshaft timing mark is at TDC for the No. 1 piston, and that both camshafts are in alignment using the camshaft alignment timing tool. NOTE: A slight adjustment of the camshafts to allow the insertion of the camshaft alignment timing tool is permissible as long as the crankshaft stays at the TDC location.
    
29. An appropriate camshaft sprocket holding tool can be used to move the camshaft sprocket (s) if a slight adjustment is required.
30. If a camshaft is not properly aligned, perform the following procedure:
    1. Loosen the retaining bolt securing the sprocket to the camshaft while holding the camshaft sprocket from turning with the sprocket holding tool.
    2. Turn the camshaft until the camshaft alignment timing tool can be installed.
    3. Verify that the crankshaft timing mark is at TDC for the No. 1 cylinder.
    4. While holding the camshaft sprocket with the camshaft sprocket holding tool, tighten the retaining bolt to 47–53 ft. lbs. (64–72 Nm) .
    5. Remove the tool and rotate the crankshaft two revolutions (clockwise) .
    6. Verify that the camshafts are aligned and that the crankshaft is at TDC for the No. 1 cylinder.
31. Install the valve cover.
32. Install the timing belt covers.
33. Connect the negative battery cable.

Click on the following free, direct Link. It has all the Timing Belt Diagrams you will need, complete with Instructional and Directional Diagrams to set your Timing.

Let me know if this helped or if you have additional information or questions. Feel Free to contact me at FixYa.com!

http://www.2carpros.com/car_repair_information/year/1995/make/mercury/model/mystique/1995_mercury_mystique_timing_belt_diagram_marks.htm

Note: the correct procedure for the Camshafts using an Alignment Tool and Wrench. There is no "marks" on the Camshaft Sprockets.

.

1. Remove the engine front cover. For additional information, refer to Engine Front Cover in this section.

1. Remove the crankshaft sensor ring from the crankshaft.

1. Rotate the crankshaft until the timing mark on the RH camshaft sprocket is approximately at the 11 o'clock position and the timing mark on the LH camshaft sprocket is approximately at the 12 o'clock position.

1. Using the special tool, position the crankshaft as shown.
   

1. Install the special tool.

1. NOTE: LH shown; RH similar.
   Remove the two bolts, the timing chain tensioner and tensioner arm.

1. Remove the LH and RH timing chains and the crankshaft sprockets.
   
   • Remove the special tool from the crankshaft.
   • Remove the timing chains from the camshaft sprockets.
   • Remove the right and left timing chains and the crankshaft sprocket from the crankshaft.

1. CAUTION: The bolts are different lengths and must be returned to their original location.
   NOTE: LH shown; RH similar.
   Remove the bolts and the timing chain guides.

Installation

1. CAUTION: Timing chain procedures must be followed exactly or damage to valves and pistons will result.
   CAUTION: Do not compress the ratchet assembly. This will damage the ratchet assembly.
   Compress the tensioner plunger, using an edge of a vise.

1. Using a small screwdriver or pick, push back and hold the ratchet mechanism.

1. While holding the ratchet mechanism, push the ratchet arm back into the tensioner housing.

1. Install a paper clip into the hole in the tensioner housing to hold the ratchet assembly and plunger in during installation.

1. Remove the tensioner from the vise.

1. NOTE: There are 61 links in the timing chain.
   If the copper links are not visible, mark two links on one end and one link on the other end, and use as timing marks.

1. Install the timing chain guides.

1. Using the special tool, verify correct crankshaft position.
   • Remove the special tool.

1. NOTE: Crankshaft sprockets are identical. They can only be installed one way. Refer to the following illustration for correct crankshaft sprocket installation.
   If removed, install LH and RH crankshaft sprockets.

1. Install the LH timing chain onto the crankshaft sprocket, aligning the one copper (marked) link on the timing chain with the slot on the crankshaft sprocket.

1. Position the LH timing chain on the camshaft sprocket with the two copper (marked) chain links and the camshaft sprocket timing mark aligned.

1. Position the RH (outer) timing chain on the crankshaft sprocket, aligning the copper (marked) link with the timing mark on the sprocket.

1. Position the RH timing chain on the camshaft sprocket. Make sure the two copper (marked) links align with the camshaft sprocket timing mark.

1. NOTE: LH shown; RH similar.
   Position the tensioner arms and tensioners, and install the bolts.

1. Remove the tensioner retaining clip.

1. As a post-check, verify correct alignment of all timing marks.

1. Remove the special tool.

1. Position the crankshaft sensor ring on the crankshaft.

1. Install the engine front cover. For additional information, refer to Engine Front Cover in this section.

Disconnect battery earth lead. Do not turn crankshaft or camshaft when timing belt removed. Remove spark plugs to ease turning engine. Turn engine in normal direction of ratation unless otherwise stated, Support engine. Remove, engine mounting, auxilliaty drive belts. Water pump pulley 1. Crankshaft pulley bolts 21. crankshaft pully 2. timing belt covers 3. Turn crankshaft to TDC on No 1 cyclinder. Ensure crankshaft sprocket, camshaft sprocket, oil pump sprocket and balancer shaft sprocket timing marks aligned. Timing marks on camshaft sprockets should align with cylinder head upper face. Dowel pins on camshaft sprockets should face upwards. Slacken tensioner bolt. Move tensioner away from belt and lightly tighten bolt. Remove, automatic tensioner unit bolts. Automatic tensioner unit. Timing belt, crankshaft centre bolt, crankshaft sprocket. Crankshaft sprocket guide washer. Slacken blancer shaft belt tensioner bolt. Move tensioner away from belt and lightly tighten bolt. Remove balancer shaft belt.

Installation
Ensuring timing marks arligned. Note timing marks on camshaft sprockets should align with cylinder head upper face. Exhaust sprocket mark is on recess, but inlet sprocket mark is on tooth. Note: to check oil pump sprocket positioned correctly, removing blanking plug from cylinder block. Insert 8mm diameter Phillips srcrewdriver in hole. Ensure screwdriver is inserted 60mm from face of cylinder block. if screwdriver can only be inserted 20mm: turn oil pump sprocket 360°. Insert screwdriver again. Fit balancer shaft belt in anti-clockwise direction, starting at crankshaft sprocket. Slacken balancer shaft belt tensioner bolt. Turn tensioner clockwise to tension belt. Tighten bolt to 15-22Nm. Apply thumb pressure to belt. Belt should deflect 5-7 mm. If not repeat tensioning procedure. Install crankshaft sprocket guide washer, crnakshaft sprocket. Tighten crankshaft cente bolt. Tighten torque:110-130 Nm. Note ensure crankshaft sprocket guide washer is fitted correclty. Oil treads and contact face of crankshaft body before fitting. Check tensioner body for leakage or damage replace if necessary. Check pushrod protrusion is 12mm. If not replace automatic tensioner unit. Slowly compress pushrod into tensioner body until holes aligned. Resistance should be felt. Place flat washer under tnesioner body to avoid damage to body end plugs. Retain pushrod with suitable pin through hole in tensioner body. install automatic tensioner unit to cylinder block. Tighten bolts to 22-27Nm. Fit timing belt in anti-clockwise direction, starting at the tensioner pulley. Slacken tensioner pulley bolt. Turn tensioner pully clockwise to temporarily tension belt. Tighten bolts to 43-45Nm. Turn crankshaft slowly 1/4 turn anti-cockwise. Turn crankshaft clockwise until timing marks alligned. Slacken tensioner pully bolt. Fit tool to tensioner pulley. Tool No 09244 28100. Apply clockwise torque of 2,6-2,8 Nm to tensioner pulley. Tighten bolt to 43-45Nm. Insert special tool in timing belt rear casing. Tool no 09244-28000. Screw in tool until pin can be removed from automatic tensioner unit. Remove special tool. Tool nr 09244-28000. turn crankshaft two turns clockwise. Wait 15 minutes. Ensure timing marks aligned. Check extended length of pushrod is 3,8-4,5mm. Install components in reverse order of removal. Tighten crankshaft pulley bolts, Tighten torque 20-30Nm

Ford TSB 99-25-4 provides the following corrected information:
To achieve proper timing belt tension on this engine, Ford says the camshaft sprocket bolts should be loosened enough to permit the sprockets to turn freely on the camshafts. Once this has been done, rotate the crankshaft clockwise so cylinder No. 1 is at top dead center. Then, install the camshaft alignment tool in the camshaft slots to hold the cams in place.

1. Back out the tensioner bolt four full turns and position the tensioner so the locating tab is at approximately the 4 o'clock position. Line up the hex key slot in the tensioner-adjusting washer with the pointer that is located behind the pulley.
   
2. Working counterclockwise from the crank sprocket, install the timing belt.
   
3. Rotate the tensioner locating tab counterclockwise and insert the locating tab into the slot in the rear timing cover.
   
4. Position the hex key slot in the tensioner-adjusting washer to the 4 o'clock position.p>
   
5. Tighten the attaching bolt enough to seat the tensioner firmly against the rear timing cover, but still allow the tensioner adjusting washer to be rotated using a 6 mm hex key.
   
6. Using the hex key, rotate the adjusting washer counterclockwise until the notch in the pointer is centered over the index line on the locating tab. (The pointer will move in a clockwise direction during adjustment).
   
7. While holding the adjusting washer in position, torque the attaching bolt to 18 lb-ft (25 N.m).
   Note: If the pointer does not remain centered over the index line during final tightening, loosen the bolt and repeat the procedure beginning with step 4.

You are quite right, there are no timing marks on the camshaft pulleys. One of the marks on the crankshaft pulley, the one that is furthest counter-clockwise, lines up with a raised mark on the oil pan,at about 5 O-Clock as viewed from the front. The special tool to position the camshafts is a straight bar that aligns the slots on the rear of the camshafts. These are supposed to be aligned before the belt is removed. If the engine is turned without the belt installed, some of the valves can be damaged. Hope this helps.