So my questions here are:
1. Do ALL 240 calipers have the dimple/pin punch marks??? (If so I've somehow missed them, or the calipers were bead blasted too much in the reman, distroying the marks)

No, just front Girling. Haven't heard of any missing the dimples, but your view of the reman industry isn't likely to be any brighter than mine.

2. When the reman folks screw up and mis-match caliper halves, are there ALWAYS certain of the bleeders that do not bleed? i.e., is it always the center two as I am noticing, only one, or can it be any combination??

No, the mis-matched calipers do eject brake fluid. They don't lose the air. That's because the bleed screw winds up at the bottom, instead of at the top, of the air pocket. You've been there before, so it will come back to you.

If you decide to push the air out with the pedal, be prepared to buy a new master cylinder and repeat the whole mess. Yes, I realize there will be folks who say they know how to do it and succeed. There are a lot of variables, mostly in how long it has been between fluid changes.

My impression is it sounds like you have an obstruction. I think there was a thread a couple years ago where someone bought calipers with one or more plugged bleed bores. We really have to inspect these things they call "remanufactured" and keep in mind how much they could possibly pay the labor and still make a profit from you.





--
Art Benstein near Baltimore

Time may be a great healer, but it's a lousy beautician.