2007 g56 to 48re swap
 

I'm going to swap a 2007 g56 truck to a 48re. G56 just cant handle the power now. Have a few questions for anyone that has done it or has any insight. I already know I have to swap trans tcase engine adapter ECM steering column pedal assembly ect. My question is wiring. I have a 2007 48re truck to do the swap from but I'm trying to figure out if I can just swap the engine/tranmission harness or if I have to swap the whole dash harness. The 2 wire connectors on the firewall of the g56 truck are the same but are missing 2 wires out of each plug making me think that I have to swap the dash harness.
any insight would be appreciated