Greg , is this still on the factory provided main line machining or did you have it redone ? I had a similar issue, stock 440 block , added studs and linebored for the studs because the torque spec for studs is greater than bolts. I put in the crank and it would lock up when #3 was torqued to spec, I hadn't opened the cap holes on #3 BEFORE the line bore, I ream to 17/32nd, I did it afterwards.

I finally figured out the cap was cut crooked by the shop , they all were, and it allowed the studs to straighten out the cap when torqued because the block side of the cap wasn't parallel to the spot face where the bolt/nut clamps against the cap.