[rocketraider]

I think I'd stick with a factory 4 barrel intake. The car has a Slim Jim automatic transmission which is very sensitive to throttle valve rod adjustment. You stick a 3x2 intake on there you'll have to figure some way to get that adjustment right, and if it's off the transmission will do all sorts of hateful things.

You sure it's more than a surface crack? If it is a substantial crack, it will create a vacuum leak. Try spraying some WD40 or such on the crack with engine running. If engine speed changes, you have a leak. If not, you should be OK.