I have an Edelbrock Performer cam, intake and timming chain on my beast (with a 600 cfm holley 1850). If I were to do it again I would use the performer RPM set up. I knew jack when I built the engine (6 years ago), I thought I wanted off idle to 5500 rpm power. A mustang II weights nothing and it needs very little torque! The other reason I did it this way, was the smog legal issues. In my area SMOG has arrived and my darn car is exempt now! If I were me 6 years ago here is what I would do: Performer RPM manifold, Performer RPM cam, 1405 Edelbrock 600 cfm carb. The RPM requires 9.5:1 compression and high volume oil pump and adjustable rocker arms. High performance pistons too. The RPM set up is dynoed at 367HP (with RPM heads and 1407 750cfm carb). The performer set-up is dynoed at 275HP. I am very happy with my performer set-up, but I would do the RPM package for more horse power. 1500-6500RPM power does not mean it does not make any low end power, it just makes the most power between 1500 and 6500. I thought the car would be a dog around town with the RPM stuff ,this is not true. If you went to a victor or a torker you would then lose your bottom end stuff but, RPM on a little II is no problem. If you had a Torino or something huge, you would need the extra torque of a performer to pull around the fat pig! I know this last comment will cause some arguing but, I would definitely recommend a Edelbrock carb. Holley's are all fine and good however, Edelbrocks are amazing! A Holley is infinitely adjustable, what this means is guys like you and me can %&*# them up real good! Edelbrocks just drop on and work right out of the box. Holley realizes this and has come out with an "avenger" carb, it rocks but is not available as a rebuilt unit. They cost huge bucks! The new "avenger" is a Holley for the common man, and it can not be adjusted too much (like an Edelbrock). Advantage cheap rebuilt Edelbrocks (shinny old Carters). Hope this helps you out