My boat is a 1977 (hull #42).
This past spring, I disassembled my mast down to a bare pole and had the yard's paint shop strip it to bare aluminum and repaint it. During the early sanding, they determined that the primer and paint were consistent with AwlGrip, which is what they used to recoat it. The process was complex, involving cleaning, chemical etch, primer, and three coats of paint. Glad I decided to let the pros do it, despite the $2k price tag!