Charles,
I'll post some pictures of the radiator tomorrow. After I got it from Mustang Barn, I had an NOS core put in, so that's the only modification. The original core was too dented.
I could consider swapping for a radiator closer to my own build date. Mine is June 19, 64 and auto with A/C. The early radiator I have "4AB", has the B1 marking on the strap that I've never found a reference for. I do know the mustang it came out of had factory A/C.
Chris