7200 rpm for a power peak is pretty impressive given the fact that you had fenderwell headers and a borrowed carb. I'm assuming the intake is "out of the box"? With a ported intake, a big carb and the correct headers you'll pick up at least 50 if not 75 hp.

Good luck with the car, it should fly. Even if you have too much gear in the car you can just run it at 3/4 throttle until you get comfortable with the extra power and then back off the gear when you're ready to go full throttle.

One thing to watch out for is converter slip as you reduce gear ratio. A low 9 second car that runs at the local track has been fighting that. He dropped from 4.88 gears to 4.30 gears and the trap RPM barely budged since he had more slip. So you have more than one variable in the equation.