I'm a big wiring nut and had just recently finished up my project of putting a VHR/HR hybrid setup in my first gen sedan..it's the chassis I started with in 2006 that has stuck to me like glue.
Did a little research and ran across your youtube page and thought what the hell why not...
Picked up this guy with 19k miles..buying a few little missing pieces and currently tearing into the harness. I already have the 370z 6mt in my sedan now so that part is done. Picked up the jwt flywheel and studying the harness now. This wiring is a LOT more serious than I wanted it to be lol. I actually may have to find the entire dash with harness from a Q50/Q60. You can do the rest of the wiring to get the car to start in the empty TCM connector..ignition relay runs through it. Looking forward to what you're able to work out with wiring, looks like you're almost there!