RobbieTunes, fleslider, rccardr - thanks for the info and inspiration. I started work on the '87 Master?, and although it looks like the original paint was stripped before the bad black paint job, I can see white and yellow overspray inside the head tube and seat tube. Based on that, I'm going with '87 Ironman Master unless proven otherwise. It does appear to be a 62cm frame measured to the lowest point on the seat tube opening as per RobbieTunes, with a ST c-c of about 60.4cm. I checked the standover and I can just barely straddle the top tube, so I'll give it a shot. A 58cm or 60cm size would be ideal, but I'm sorta done with frames any smaller than that. I have a 56cm Steelman Stage Race from 1998 which I love, but it took some work to get the bars up to where I need them.

Question about a repaint/powdercoat: It looks like the frame was stored in humid conditions long enough to have a little surface rust inside the tubes. What would y'all recommend to take care of internal rust in preparation for a powdercoat? Should the frame be first stripped and then soaked in an oxalic acid bath before blasting?

This may be getting away from purely a Centurion S/N post, so feel free to redirect this conversation if necessary.