Long tube headers ( pacesetter 1 3/4 is perfect), remove the cats and get a mandrel bet 3” y pipe, magnaflow or borla muffler, Summit 20% UD pulley, 87mm TB, Intake, and a good tune. That will get you 400 CRANK horsepower which comes out to around 305-310 RWHP.
Gears don’t go be power but ****...