Here is a picture of the inner brace for the mirror. I can’t guarantee that the bolts you see are in the correct position as it’s not my picture, but you’ll get the idea of how it’s done.
Phil Moderator, The Engine Shop, Interiors and Project Journals
1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes Project Journals Stovebolt Gallery Forum