i blew my headgasket and replaced it. now i dont have any pulse going to my fuel injectors or cold start injector, no gas from the fuel pump either. i hot wired my fuel pump and it worked so i no its not shot. i can get my truck started if i hot wire the fuel pump and hook up a pulse generator to the cold start injector, but only for a few seconds. Is it a crankshaft position sensor? camshaft position sensor? or the computer? its not a 96' its an 86'

The fuel pump is enabled only when the mass air flow vane has moved due to air flowing by it.
You need to check the connections at the MAF and make sure all is copasetic. There are easy to follow procedures to do this. there is also a jumper at the check connector to test the pump.
As far as getting you injectors to fire there seems to be a more serious electrical malfunction that may be the root of all your problems.
Check your wiring carefully. Good luck.
The reason for the fuel shut off switch is if the engine isn't running you don't want the pump to be pressurizing the fuel rails especially if there has been an accident.

check the cam sensor