1994 s-10 blazer wont start

i recently bought a 1994 s-10 blazer with 4.3 vortec in it ive replaced fuel pump i need someone to tell me what firing order is and number 1 piston i can get it to start where it is at on timin now if i keep pourin gas into intake but wont stay runnin if i quit doesnt pop or snort all plugs distributor and wires are new

Make sure the injector fuses are intact, and test the fuel pressure. The system needs to maintain 61 PSIG to start. The fact that it runs with you administering fuel means that the ignition system is functioning. This also likely means that the ECM is getting the ignition signals it needs to operate the injectors. The injectors need to have a power source and the pump needs to provide fuel at correct pressure for the injectors to operate.