camaronut,
Thanks for your input.
I have successfully removed couple mirror glass pieces by soaking the mirror body in lacquer thinner overnight. I use a 4"x8" tin bread pan and fill it with enough lacquer thinner to completely submerged the mirror body, and seal the pan with Serrand Wrap to minimize evaporation of the thinner. Once I am done, I can filter and recycle the lacquer thinner. I prefer lacquer thinner over gasoline. I use a narrow thin blade flexible tool wedged between the mirror and body to pick the mirror out by slicing thru the (4) blobs of RTV adhesive sealant towards the (4) corners of the mirror. If the RTV sealant is exposed to lacquer thinner for about 24 hours, the mirror glass can be removed with little effort. The tool is an old artist oil paint mixing blade (thanks Mon!). The closest alternative blade in thickness and size would be a feeler gage.
One thought/suggestion to remove the mirror body from the pedestal mount: Cut (2) pieces of plastic sheet material into a "U" shape (maybe plastic cut from a milk jug or antifreeze jug) and insert them about the stem of the swivel ball, against the mirror body and the rim face of the pedestal mount. Wedge and tap in two pieces of tapered wood shims in the joint to "press out" the swivel ball from the pedestal. Using a heat gun to warm up the cup area on the pedestal may help. I'll look for pics from the last door mirror I restored, but the head of the swivel ball has fine serrations that slice, bite, and hold in the pocket of the pedestal mount when press together. You can use JB Weld adhesive to reattached the ball stud in pedestal. The trick is to separate this joint without damaging either component of the door mirror!
Dave