Like the tittle says, how can I do this? Since one obviously has 6 and the other one 8?
You are kidding right?Easy, just change the crankshaft... It takes a few hours but not too hard to do. Just drop the transmission, the K member, oil pan and pull out the old one and slap a new one in... Beings your there you really should put a new oil pan gasket though and maybe grease the throw out bearing. Be really careful with what your doing though.... you can mess up a throw out bearing pretty quick if you dont use Royal Purple or Redline grease.
ditto. Thats alot of work. Even on an ole pushrod motor thats still alot of timeYou are kidding right?