It is glued in. 3 dabs on the swivel mechanism if I remember right.
I hit a stone mowing about 100 feet from the house once. The stone went into the open garage door and hit the left mirror in the middle of the glass on the '81. I couldn't do that again for a million bucks, not that I'd want to.
Several sources sell the mirror glass and some say that they can properly date code them. For some reason they can't do the late C3s though, unless something has changed in the last few years. I got my new glass from Paragon and had the local auto glass shop glue it in. They didn't even charge me.
You might try a heat gun on the glass to soften up the glue and use a hook around the edge to pull gently on the glass. You will probably have to break the glass though. Be careful with heat to not get the mirror housing paint too hot.
Tom
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