I've been on a long break on my car, almost 2 years, but i think this winter is going to give me some time to work on it. One upcoming problem i am facing is wiring my car together. I have the ECM programmed and VATS removed to allow start up. SPEARTECH pulled out the wires from the GTO harness (06 gto donor drivetrain) and added a OBDII connector so engine wise i think i am covered to get the engine running. I need advice on what i need to get everything else to work, maybe someone can point me toward an easier solution than bonding wiring harnesses together.

I am doing a 4th gen interior transplant, including dash. My car has power everything and i would like to keep it this way. I am somewhat intimidated going into this project, wiring is not my strong point. I also know that gauge communication between the LS2, and the LS1 gauge cluster from my 00 trans am will also have communication problems.

so summary.... 06 gto engine harness, i have a donor 00 trans am complete, and my original 88 iroc harness, and need them to work together lol

Am i best to try and just wire something on my own?
Blend interior harnesses?
Custom gauge cluster best?
input please....