392 stroker oiling problems

Did the same mains spin the second time? If so and the engine is out of the car, drop the pan, pressurize the oil galley and look for leaks from the main oil gallery at the pan rail. You could do it in the car but it's messy and a PITA. Sounds like you may be the victim of oil gallery core shift and the stroker clearance notches broke through in a couple small spots.