I don't have a lot of time right now, but it shouldn't be too hard to find or remove everything smog related. To answer your other questions really quick, for a price I would venture to say about 2-3k. Might even be a little high. And to add the 4 barrel should be as easy as removing the manifold/carb and replacing. Just don't go too big for the carb as these engines weren't really the most performance oriented. I'd say that maybe a 500 cfm would work well, 600 probably being the max. I'm sure someone else can chime in with more specific/better answers though....