Craftsman instructions I need to know how to set my wrench to 780 inch pounds the wrench only goes to 250

There are 12in/lbs in 1ft/lb.
On a range of 16-20 in/lbs, I would set to 18in/lbs or 1.5ft/lbs.
That's a really low torque. I don't recall seeing anything but specialty torque wrenches for that small an amount.

On a 3.4L grand am, my info says 89 inch lbs. You local auto store will sell torque wrenches, inch pounds or ft pounds. For small torque, I use inch pounds torque wrench. If you snug it up, you should be ok. I'm not saying crank on it for all your worth, just snug it up or use a torque wrench. Just keep an eye out for leaking?

Use an Inch pound torque wrench (very cheap to buy), then set it to the conversion of 9.5 ft pounds to inch pounds which is 114 inch pounds.

in INCH pounds 220
that's inch pounds, not foot pounds
valves adjust at .004~.006

I strongly recommend you consult a repair manual for the timing belt install procedure. Depending if you have a hydraulic or mechanical tensioner for the belt, the procedure is different. If you register for free at www.autozone.com, listing make, model and year, you could find the procedure under "repair guides".
Here is a shortened guide: Align notch of crank sprocket with the arrow on the oil pump housing, then back off 3 notches or teeth, (counterclockwise to back off).
Align notch of cam sprocket with mark on the inner belt cover-it is at top of engine-notch on cam will be almost straight up.
Move crankshaft to 1/2 notch before arrow on oil pump housing. Install belt starting at crankshaft, then around water pump, then around camshaft sprocket last.
Move crank to TDC (notch right with arrow) to take up belt slack.
Reinstall tensioner, and tighten fasteners as follows: Mechanical tensioner-250 inch pounds.
Hydraulic tensioner assembly pulley bolt-50 foot pounds. Hydraulic tensioner assembly and pivot bracket bolt-23 foot pounds.
Remove tensioner plunger pins-for either mechanical or hydraulic tensioners. Tension is correct when plunger pin can be removed and replaced easily.
Rotate crankshaft at least two revolutions, and recheck timing marks.
Reinstall timing belt cover, engine mount bracket, engine mount, and crankshaft damper. Tighten crank damper pulley bolt to 105 foot pounds.
Reinstall drive belts and accessories.

I know the info on the tensioner is confusing: why you need to consult a repair manual or register at autozone. You have to compress the plunger on the hydraulic tensioner after removing it and insert a pin (a very small Allen wrench works-5/64 inch Allen wrench). If a mechanical tensioner, you will need an 8 mm Allen wrench to rotate the tensioner counter clockwise (this is before or after removed from engine), the use a 1/8 inch or 3 mm Allen wrench to insert into plunger hole, to hold the tensioner retracted until installed. See what I mean? Post back if unclear...or just find the repair procedure. Sorry, no diagrams available for me. I'm too old and crochety-lol.

8.8 ft lbs. use your calculator. 106 divided by 12 Foot/ Pound Torque wrenches are not accurate that low, thats why its inch lbs.

1 foot lbs = 12 in lbs
2 foot lbs = 24 in lbs and so-on.....
Hope this helps you....

if you dont use hand tools often you should never trust the torque from impact wrench you should always recheck with tension wrench for correct torque specs
or at least hand tools such as breaker bar, spanner, ratchet
depending on what your doing up and diameter of bolt or studd for what application

Try turning your line air pressure up to at least 90 pounds
Most lug nuts are tightened to 85 pounds or higher

Make sure you have at least 90 pounds of air and if you do you need to oil the wrench air tool oil pour some in the where the air line hooks up ..air tools need to be oiled daily cause compressed air cause water vapors to build up when you use it and then when it sits it begins to rust a bit and the oil stops this ...