I recently bought a 1974 C-10 stepside, the truck has been rodded out and upgraded, it has the original 350 with a new camshaft, headers, exhaust,.... What's the best Holley Carb to use as a temporary until I swap out next year? It has a 750 pump on it which is burning gas like heck, I need to downgrade and get better gas mileage any help please?