O.K. Jeep guy's here ya go a question that might be easy but I can't answer it!! I picked up three engines today, The guy I got them from has had them for awhile in his shed he said the guy he got them from said two were 304 and one was a 401. Now how can I tell? The casting on the blocks all say 360! I have heard all the blocks from 304 to 401 are the same but would they be marked differently??