i have a 93 z28 i obtained and the inside wiring harness was trashed

i got a 95 z28 fuseblock harness plugs all matched except a couple of wires here on the fuel pump, and where the key switch turns it was missing 2 wires also does n e body know if and or how to make this one work? if possible and it has the obd2 plug.
after i plugged it in it turn the car over,had no spark,fuel pump would not kick on and the scanner i had would not read the comp. there must b a couple of wires to move and a plug or two to change but pls, need info!