Truck Forums - Misfire that i can not find the cause of

I have a 1996 gmc sierra 1500 2wd ext cab 5.7 . I have a cylinder 2 misfire that i can not find why . Im a mechanic for a living and this truck is stumped me . I have replaced the spark plugs ( oem ac delco) , spark plug wires , distributor cap, rotor button , distributor , camsensor , cranksensor , upgraded spider injector , timing chain , fuel pump . I did all this before i bought a suburban with 90,000 miles that ran great and i swapped engines thinking it would cure my problem . I still have a misfire since then i have replaced intake gaskets , throttle body , spark plugs , fuel filter , wiring harness , mass air flow sensor , thermostat , coolant temp sensor . I dont know what else it can be besides the computer and help would be greatly appreciated