There's few things to consider. Some depends on your state laws.
I have a '78 L82, and since it qualifies for "historic" status in my state, it's exempt from emissions testing. I removed the catalytic converter and installed a true dual exhaust with low restriction mufflers. That freed up horsepower. I don't know how viable that me be for you, since I think Chevrolet stopped making the frames with the extra opening for duals after about '78. You can certainly check on it.
I also removed my EGR equipment and installed an Edelbrock Performer intake manifold and had my Q-Jet professionally rebuilt. I'm running stock exhaust manifolds and the car runs great...far better than before. I don't know what horsepower the engine is putting out, but I'm well satisfied with it.
You can investigate a system like Edelbrock and others sell...their Performer package, including the intake, camshaft kit, carburetor and aluminum cylinder heads. Their Performer intake will fit under an stock Corvette hood, their others won't unless you're installed a custom hood, or maybe a very low profile air cleaner. Contact Edelbrock and they can design a system for exactly what you want...everything is dyno matched to your goals. Companies such as Holley can do the same for you. You can keep your original heads and still get a good system that will work. Getting headers may not even be necessary unless you really want them. I've always felt headers are an unnecessary pain unless you're after max power. For a street car, I think they're overrated.
With a system package for your car, you save the original parts and swap them back if you want at a later date without too much trouble.
