Nelson Performance (The owner of this forum) can set you up with a harness or you can modify your stock 97 harness to run the Gen3 engine. The Gen3 A/C compressor will fit in its stock location with a BIG notch taken out of the frame of your 97. You can also use your 97 A/C compressor and lines in their stock 97 location with an adapter bracket kit. There is NO need to run 2 PCMs. The 12200411 PCM will run everything on your truck just fine by itself.

Jeff