'67 283 2V Rochester Carb question

[Duluth67]

Currently working on a '67 K20 with a 283, 4 speed. I had the engine rebuilt, 60 over, "rv cam", put true dual exhaust on. Engine builder said the heads were "4 barrel type" but I had a 2 bbl intake mani.

I bought a rebuild rochester 2 bbl for (autoline brand) and installed it with a new gasket.

http://www.autozone.com/fuel-deliver...3032_123660_0/

Set timing with vacuum gauge. Set up with manual choke, as stock would be.

Truck always starts and idles nice, but when shifting gears, I will get a pop through the carb and a hard stutter. Also when cruising, there seems to be a slight surging.

What would I do to solve these running issues? Also, don't know what these trucks would have/get for fuel mileage/power, but right now it needs full throttle to go up hills and is getting around 7 mpg. 4.56 gears. Rockwell T221, SM465.

My original thought is maybe it is running lean, but I don't know how to tell for sure. If it is, could a main jet fix the problem, how do I know what one is in the Autolite? Better to switch to 4 bbl. If so, which one?

Thanks!