I have a 1996 Chevy k1500 that had a 4.3 vortec v6 with an nv3500 behind it I pulled the v6 out and put a 5.7 vortec v8 with the wiring harness and ecm from the 1998 Chevy pickup it was pulled out of. I got everything hooked up and ran wires to the starter with a button start it there’s no codes...