New 73 Duster

Hey guys, somewhat new to the site and seeking some advice. Have a 73 Duster and here are the specs:

360 .030 over
Speed Pro flat top pistons
69 X heads, light porting
11:1 compression
LD340 intake
MP .528 mech flat tappet cam
MP roller rockers
904 3000 stall, 8 3/4 3.55 gears w/ a sure-grip
750 holley
Mopar electronic igntion, 4 pin ballast
Headers and dual exhaust.

Idles good and choppy. Lots of power at WOT. Unsure of it's track time yet but it has a stumble at around 2-2500rpm. Live at 6500 ft and car came from 4900. Have a 600 edelbrock that I could throw on, is 600 a little small? Came off running and have the stock jetting for it.

Needs other fixes like the bushings, the pinion backlash needs to be tightened, alignment, other doo-dads. Tranny shifts pretty harsh, I may lower the line pressure or get another shift kit.