Update. I got the wiring all run for the reverse lights, neutral safety, trans brake and paddle shifters. It all works flawlessly besides the paddle shifters which I don't have switches for yet. The trans brake is a bit underwhelming as the stall is low and doesn't flare high enough to make power. The PCM codes have gone away for the most part. No check engine light, but there is a P0750 code for the missing 42RLE solenoid pack. I have a plan for that, but if that doesn't work, I can always do a manual trans computer. Also, it is worth noting that I have been running successfully with an aftermarket hall sensor for my crank pickup. The factory PCM doesn't seem to know or care about the sensor. I have had no issues with drivability or codes in the PCM relating to the crank sensor.