Hello I need to replace the rear view mirror on Lincoln Mark VIII 1998,I want to keep the old telescopic arm attached to the windshield. Can I detach only the mirror to use the new one attached?

You named your rear view mirror 'Reginald'?

The mirror is affixed dead centre and about an inch down from the top.

https://www.google.com/search?q=2004+ford+explorer+rear+view+mirror+replacement

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If you are4 asking how to reattach mirror to windshield go to auto parts store and buy a mirror attachment kit. Follow directions. It should not be a problem.

it is located at side of dash drivers side page 109 of your owners manual starts your fuse information the following link is the owners manual incase yours is unavailable
1998 Lincoln Mark VIII Owner Guide 1st Printing

This is a question Instead of an answer, which is I need explicit steps on how to remove mark viii PCM. can anyone help me with this.

Most cars have the rear-view mirror and the little metal mount that it slides into. If the whole thing has fell off it is an easy fix.
Go to an auto parts place and tell the counter person you need the glue to glue your mirror mount to the windshield. They will know what to give you.
Then you clean the spot the mirror was hung with alcohol. Let dry
Then follow package directions. Basically you do a dab of glue on mount and press to windshield and hold for a bit of time. Then you wait like 12-24 hrs before sliding the mirror onto the mount.

On the other hand if you are asking for a new mirror you can get one from the Buick dealership - parts dept. or a junkyard or just attach any kind of rear-view mirror. Sorry I can't help you if you have a wired mirror.

Only two possibilities, one is the vacuum hose that goes from the top of the engine, over to the passenger side of the engine and through the firewall is detached from the engine, or has a break somewhere-the other, more likely cause is the blend door arm is broken, they are notoriously weak and break easily and often on Generation 2 Mark VIII's. You can manually open the blend door if this this is the issue, but replacing it with a stronger, improved version is really the only fix.

should just push in to the bottom of the washer tank, if this one is located inside the front fender, you'll need to remove the plastic inner fender-well to access

The button is locked into the mirror shoe by a flat spring. Find the notch at the bottom of the shoe and insert a small flat screwdriver to push the spring away from the button. Some force may be required.

Must be a loose nut on the wipers, or the arm on the wiper motor.

To remove