I took out my Crown to check something and out fell a few parts

A little searching showed that they were the shims for the back yoke guides. No problem, put them back in, check the fit, tighten down the screws... All fine except for one missing screw and that's apparently not floating around in the case anywhere...

So instead of taking one out and trying to figure out what it is, I thought I'd ask here first to see if anyone knew what size this machine screw is so I can get a replacement.

If not, I'll go digging And gees, how did they tighten those back ones?

Thanks...

By far, the least agravating way to tighten the rear screws on a Crown is to remove the bellows and standard as a unit. The screws are then easily accessed. Remove the back. Only a couple of clips to remove, bow the bellows mount plate until it pops out. Don't mess with the little tabs on the sides. Bend 'em, they'll break off, bad news!
Drop the bed, slide the standard off at the track joint. Put it back in the same manner and you're done.
About 15 - 20 minutes work.
Check your messages about a screw.