2000 Regal GS - Auto-dimming rearview mirror "clip" installation issue
 

Hey there!
Just bought a 2000 GranSport with 152kmi and it has a fallen rearview mirror.
I bought a glue kit and have the metal "button" reinstalled on the glass, but the rearview mirror uses some "clip" design I've never seen before and cannot for the life of me figure out how to reinstall it without braking the glass.

This isn't the normal "slide on, tighten down" design, you have to hold the base of the mirror post against the "button", the snap this big "C-clip" looking thing on to hold it all together. Never seen it before.

Any help appreciated, thanks!

~M