okay, last question before I make my mind up. If I'm going with the b20 bottom end........ and I plan on putting the sc on. would I be better off with the b20 block and a b16 head, or a gsr head? and would it be cheaper to just work the b16 or b18 block to make it better than the b20 block? if so which set up is best and the least amount of money?