I have an 89 GTA and I'm getting it ready to install a shiny new LT1 w/4L60E. Now i've already done the swap before in a 2.8 Camaro where I didn't care about keeping the old wiring harness, so i just stripped it from the body portions of the harness. I want to keep the TPI wiring harness/ecm so i can use it with the accompaning TPI engine in another vehicle. How have you done it because the two intertwine with each other throughout the harness?

 

Some years do, some years don't, the only wires on my 89 GTA that were intertwined with the engine harness were the wiper resistor wires, seems those 4 wires were tied up into the engine harness. What i did was simply cut them and seperate those wires out of my engine harness. Other than that, no other wires should be intertwined with the engine harness that can't be unplugged.