Ouch,
Etched glass. Someone didn't plan on those mirrors coming off!
I'm not aware of any chemical way to dissolve epoxy. But you may want to try a dab of the strongest paint remover you can find & see what happens, you might get lucky. Or the epoxy may just sit there and laugh at you & your paint remover.
Otherwise, if you can't get a razor under it to scrape or chip it away, if it is really stuck, then my suggestion will be to remove the glass from the car & carefully use a wire wheel. Whatever you do, don't breath the dust while wire wheeling epoxy.
If the paint remover works, please get back to us & let us know, it would help others when they're faced with the same problem.
your friend on the PIBB, George
thanks for the laugh Coz (aka Cliff)
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