You bring back many memories of trying to get some 70"s sport mirrors on my 67 GTO, because I always liked the look and because I wanted to have turn signal LED's in their glass.
https://forums.maxperformanceinc.com...d.php?t=624572
Tried multiple base legs to see if any came close???? NADA.
This necessitated changing the angle of the base support leg and presented some careful grinding of the bottom of the base to match the door contour. Then had to create an angled washer/spacer for the inside to let it all fit and lock down with being tight enough.
It were fun.
Charles