Take fatweed's advice and check the casting #'s from your heads. There are a lot of so called "double hump" heads out there. Not all of them are the performance heads. There is also many misconceptions on what the casting mark actually looks like. I know of several local guys that have heads that have 2 humps on the casting mark, and claim that the have the "feulie" heads, but when the #'s were checked they were the standard heads.
Just to throw in my 2 bits, I would suggest a 4 bbl. carb, spread bore perferably, for best economy and power. You'll be on the smaller primaries in normal driving, but still have the extra power in the secondaries when their nececcary (like passing, goin up steep hills, etc.).
