[Grumpy old man]

yes the V8 cross member fits the frame further forward , many guys just use the 6 position to drop a V8 in it's the fast / cheap way out . If you just want to have a V8 to go blasting around in it's fine . To go V8 correctly you'll need a cross member , drive shaft , engine perches , a better radiator , a fan shroud , and if you want to do it while the cabs still on the frame well good luck cutting and removing all the rivets from the old cross member and fitting the V8 cross member in . I did mine on the bare frame . It all depends on what your trying to have when it's done . and how much you plan on dumping into the truck .