Why bother with a carb? They waste fuel and reduce HP. Install a fuel injection system that uses an O2 sensor if possible. Doesn't cost that much more than a carb either. So called fuel hog performance vehicles even with cam upgrades etc. They deliver surprisingly good throttle response, power and economy with a fuel injection retrofit. Next step is to get rid of the three speed automatic or the four speed manual. And install a four speed automatic with lockup torque converter. Or a five or six speed standard with over drive.