Mo power for my Mopar 340...

After investgating my new 67 Dart 340 4 speed, I found that I have a 340 built after april of 1972, which would make it a low compression 8.5:1 motor with a cast crank (it has a damper for a cast crank). It has 3418915 heads with 1.88"/1.60" valves, a 600 CFM Edelbrock carb, and headers with 2.5" exhaust pipes (no H crossover)... I've been told that after it was rebuilt that 9.5:1 was the compression with forged pistons... Even though it has a good sounding cam (which isn't known), my thoughts to improving the output would be: 1) 1.6:1 roller rocker either stainless steel or aluminum and or, 2) 750 CFM carb... What is anyone's thought on that?.. Is 750 CFM too much?.. They did use Thermoquads, which I would guess would be close to 750... Would I have clearance problems with the pushrods in the heads?... I believe this was a de-rated motor at 245 HP@4,800 compared to the previous high compression 275 HP in 71 and early 72... Thanks..