Rear view mirror mount removal

[Craig D. Niederst]

I got a good deal on an electrochromic rear view mirror (free) from a '98
A4, and I am attempting to install it in my '92 100S. The new mirror uses a
round style mirror mount versus the more traditional mount currently on my
100. I have the wiring ready, but the only problem is I cannot remove the
old mirror mount from the windshield. I have tried to pry it off carefully
with a razor blade, but I cannot get the blade behind the mount. I tried to
just pull it off with the mirror attached, but I'm afraid that I am going to
break the windshield. Anyone done this before? Any tricks? TIA.

Craig
'92 100S (99k)
'86 CGT (214k)