If it's not too late, the absolutely best carb setup I've come accross for these engines is a 2 stage 2 barrel (like half a 4 barrel)used on some Vegas, Pintos and Chrysler K cars. Tom Langdon (Langdon's Stovebolt Parts) also sells rebuilt ones for about $65 I think. He also sells the adapters to bolt them onto a stock manifold. Even installing one of these will make a noticable difference in the engine. If the engine is in good condition it will probably accept 2 without a problem. The beauty of these carbs is that they have a small primary with a larger secondary. That gives you great fuel economy and still improves the overall performance. I have a pair of them on my 261 in a '50 pickup with a little cam an it hauls butt and still gets 20 + mpg. I also installed one of these carbs on a stock '62 Biscayne and it worked very well. Neither application required rejetting the carbs. They're great!
