Should I trade my swinger for a big block?

Keep The Swinger and stroke a 360. If you go to a big block, you will need new headers and a tranny plus kick down linkage. Then you end up trying to find little odds & ends to put it all together. Your radiator neck on the bottom of the radiator is on the opposite side, so you will have to have that moved or buy a new radiator. It is a big headache if you don't have a parts stash. If I were gonna go BB, I would buy a 400, 440source 500 cu inch stroker kit, and the new aluminum heads they just came out with. You could build a wicked motor for around $5000, and know what is in it.