96' 4.3 Vortec Csfi, Need Help, 911

MY 96 SIERRA WITH THE 4.3 AND 5 SPD. MANUAL MISSES UNDER MODERATE ACCELERATION. MAINLY IN 3-5 GEARS. CRUISES ALRIGHT, IDLES GOOD, CHANGED DIST. CAP, ROTOR ,PLUGS, WIRES ,COIL, NO VACUUM LEAKS,NEW COOLANT TEMP SENSOR, EGR VALVE, FUEL REGULATOR, RUN 89 OCTANE OR HIGHER, PUT IN FUEL INJECTOR CLEANER EVERY MONTH. NO SERVICE ENGINE LIGHT, YET. COULD IT BE FUEL PUMP? I CAN HERE IT RUN AND PRIME. INJECTORS LOOKED GOOD WHEN WE PUT ON REGULTOR FEW MONTHS AGO. I PUT ON A NEW PCV VALVE ALSO. I DUNNO. NEED TO GET RUNNIN GOOD FOR CAMPIN SEASON. I CAN BE E-MAILED AT [email protected].

Changed Plug Wires, Helped Great. Still Got A Very Slight Miss While Accelerating. Any Suggestions? Anyone? Not A Big Deal,but I Like To Have A Smooth Runnin Truck.