I would put the 318 on a stand and put a 340 in it, but only if you have a decent rear end in it. Even a rear end swap should be fairly inexpensive. That way the stock, #'s matching stuff is for safe keeping. If and when you ever do sell it, it will gain a lot more interest having the 340 in it and the #'s at home on the stand. Good luck, have fun with it!!
