outside rearview mirrors coming unglued..?!

aside from the feds coming unglued so too have the outside rear view mirrors on two of my buick wagons..
looking behind the glass i can see where the glass hed been glued to the tilt mechanism..
any advice on how to re-glue these..
it has been suggested to use an epoxy glue but the question arises how to clean the mirror back without damaging the mirror silvering..

thanks

I would use body panel adhesive or windshield adhesive.

update:
obtained some J-B Weld Plastic Bonder Body Panel Adhesive and Gap Filler to try regluing the mirror face back on the adjuster mechanism..
found that it would work in a sort of "get a bigger hammer" way once i looked into the inner workings..
the '92 had some silicone sealant type of bead that had come unglued to the inner mirror surface..
not having any of this sort of adhesive on hand it occurred to me to just use some industrial level double sided tape.. i have some and used it and so far, so good.. note: this stuff is rated for outdoor all weather use for gluing a heavy item to a brick wall..

the '95 was another issue..
it had some small snap in parts, one of which had degraded and part of it is gone..
i could have used the two part JB weld but went with the same two sided tape but had to build up a much thicker piece.. it is on and i'll think about how to proceed if it fails..

pix supplied on request..

FWIW, I had a truck that had flat side mirrors.  I went to the parts store and bought a pair of fisheye mirrors that attached with double-faced tape.  The tape was already applied to the back of the mirrors by the manufacturer, so that only one side needed to be peeled.  The stick-on mirrors were 4" x 6", and held on by strips that were about an inch wide and 3 inches long, with two (maybe three?) strips per mirror.

They didn't stay on through the first summer.  It would get hot outside (100+ degrees), and the adhesive would not stick.  I would walk out to the driveway and discover mirrors on the ground (usually one at a time).  The double face tape came off from both sides (from the side stuck to my original mirrors and from the side stuck to the back of the aftermarket mirrors) somewhat equally, so it wasn't just a case of me not cleaning the glass well enough before application. I tried replacing the factory tape with a 3M product, with similar results.  I re-stuck the mirrors maybe 5 times that summer.

Finally, I got a tube of weatherstripping adhesive.  I peeled off all the tape and put a couple dabs on the back of the aftermarket mirrors, held them in place for a few minutes, and then never had to deal with them again.  They were still attached when I got rid of the truck more than 25 years later, and it had been parked outdoors nearly the entire time.

will see how long this stuff survives..
it was very expensive double side tape made for hanging heavy items to brick walls or spo says the package and advertising..
have had some holding two lamps to ceramic brick like tiles for years, over my stove..
if they come loose i'll go with the two part adhesive..