I would be running M1 0w-40 or similar, like Havoline Pro DS 5W-40. Your not going to have any of the issues that might be helped by either of the other oils - unlikely to carbon / sludge, I am guessing your not trying to do very long OCI. 302 engine weak link were the rod bearings (undersized journals and the bolts were pretty wimpy also - unless you did aftermarket). So a thicker film can't hurt.
IMHO.