1983 cj7 360 running bad at 1900-2500rpm at quarter throttle

Hey guys im working on a buddies 1983 cj7 that's been swapped with a 360. He had it at a mechanic shop they put in a new cam, lifters, reworked the heads, edlebrock intake and carb, trans, distributor, coil, wires, plugs, ign control module, fuel pump, fuel filter and timing set. it runs great other that when your driving normally around 1900-2500 rpm it will jerk around and sounds like its misfiring pretty bad but that's at a quarter throttle or so. but if you floor it it wont do it. ive checked everything over. reset the timing made sure the wires were on correctly warrantied the carb (thinking it was a fuel delivery problem with the main jets but it still doing it. put new plugs again at the correct gap retorqued the rockers (some were loose). ive spent a lot of time trying to figure out his problem and im at a loss any info would be amazing.

Also it idles perfect and under heavy acceleration its great and has a lot of power. its just around that rpm range that it messes up