86 318 build

I have the original 318 with 84,000 miles on it. It has a really hard rod knock in the bottom end and smokes like a pig when i fire it up. I have another 318 out of a 86 ramcharger which we believe is in good shape (have not broken down yet, doing it this weekend) which has 302 heads on it. I was talking to a good friend and he knows a guy who has a 360 (idk what year) and he said he would possible sell it to me for $400. I might do lite modification to the 86 318 and save the rebuild of the 360 till i am older and out of college