Thanks for the reply. I'm sure I have some small machine bolts lying around somewhere and will do some experimenting tomorrow. I know I'll need something smaller than 8/32 or 6/32 with tapered, not straight, threading. My memory of working on the problem is from probably at least two or three years ago, but I'm fairly sure that the Beseler screws, just based on visual appearance, don't seem to be machine-bolt threaded; they look a lot like sheet metal screws, but apparently aren't quite the same--unless they're some non-standard size. No, I didn't force anything, so when I locate the proper fit, the holes in the enlarger should still be fine.