""3.55's with a 255/60/15 on the back Believe its a 27in tall tire.""
Mainly due to the 2500 stall, I would suggest the 650/750 vacuum secondary carbs. I would also suggest to choose one with adjustable circuits (IAB's/HSAB's and IFR's) This makes future engine modifications easier to tune.
Intake: RPM/RPM Airgap.
1970 YO7 A66 [Canadian Export] F8 Challenger 340 (Currently in shop for stroker assy.)