1989 Chevy Silverado truck won't run

HAVE AN 89 SILERADO (350 V8 ENGINE)
WENT DEAD ON ME GOING DOWN ROAD, GOT IT HOME BAIRLEY RESTARTING IT AND GOING A LITTLE AND THEN RESTARTING IT AGAIN.

I HAVE CHANGED THE FOLLOWING: FUEL FILTER, FUEL PUMP, PLUGS, PLUG WIRES, DISTRIBUTOR CAP, ROTOR, INGINTION MODULE, ONE OF THE FULE INJECTORS.

TIMING HAS BEEN CHECKED AND IT IS O.K.

CAN CRANK IT UP --- RUNS ROUGH ON IDLE --- WHEN GIVING IT THE GAS IT GOES DEAD

NEED SOME REALLY GOOD ADVISE