5.3 swap into 01 gmc sierra

i got a 01 sierra that has a 5.3 that was dropped in it. i bought the project from a guy who had to deploy. i finished mounting the engine and tranny and now im down to the wiring harness. i have the old harness and the new harness that came with the engine. he gave me a computer that was tuned by nelson performance for the 5.3 but the connectors fit the old harness only. i dont know what to do from here and really need some help. i read that you can make your own and im pretty good at wiring so im all for this. HELP is much appreciated!!!!!!!!!!!!!!!!!!!!!!!!!!!

:doofus:

Vortec 4.8/5.3/6.0 Wiring Harness Info this should get you up and running I don't know if you can find a pin out for your truck but if you could you could tie it in instead of makeing it st alone. if you email brendon from this web site he will walk you through all your issues he helped me a bunch

thanks a lot this is really helping me!!!!!

:thanks:

Does the harness that came on the engine have red/blue plugs or green/blue?

the harness that came with the engine has green/blue plugs but the computer has red/blue plugs