'68 318 to carbed Magnum 5.2: Check my checklist

Have you considered pulling the distributor and priming the oiling system until they begin to pump up? That way you don't have to keep cranking and cranking...When I prelube an engine, I'll typically rotate the engine 90* and keep priming for awhile. I don't know if it helps, but the lifters generally are quiet pretty quickly that way.