The painted area around the brake master cylinder always seems to be in poor condition at the beginning of one of these projects. My own car is a case in point. Is there a paint that will stand up to brake fluid?
A few years ago when I went to BBP in the rear, I also re-plumbed my front brakes w/ a new alum MC, adj prop valve, line-loc and eliminated the safety valve/tee. (simple is good) With all the newly bent and flared tubing required, at first there were a couple small leaks but I stopped them by cranking the nuts a little tighter. I converted over to DOT 5 silicone brake fluid which does NOT attack the paint and never looked back.