For my Chevy, I decided to upgrade to a wider inside day/night rear view mirror, so some time ago, I purchased this setup to attach to the OEM mirror bracket:
MirrorOrig.jpg

The curved adaptor didn't clamp up well to the mirror, so messed around to get it to fit better, and shortened the screw that attaches the mirror to the adaptor, so it didn't extend beyond the adaptor. I attach it all to the OEM mirror bracket, and see the mirror bounces around like crazy because it is so poorly built - the stud on the back of the mirror wiggles around. Drat.

I found the mirror shown below on eBay, and after exchanging messages with the seller, I figure it is worth a shot (good guy). I will retain the day/night option, I will give up a bit in width over the shaky mirror (8-5/8" vs. 10"):
New mirror.jpg

I like it - no muss, no fuss, and no shakes!
8.5.8vs10 mirror.jpg