Welcome to the forum.
I'd start with a few bolt on's first.
The carb swap was a good start but alittle on the small side IMO.
A 650 or 750 cfm unit would give better performance.
Headers and a free flowing exhaust system.
Install a free flowing air filter like a K/N, their worth a couple ponies.
An electric fan will free up some Hp.
Upgrade the ignition system to a MSD or equivalent.
A small cam & roller rockers would wake things up.
373 gears / posi rearend.
Street slicks or drag radials for better traction.
Goodluck, Cp