Cutting my own Harness... Questions for the experts

[knomadd]

Okay all of you LS swap wiring guru's... I need your help. I think I've got my game plan for cutting my harness sorted with a few questions still remaining.

First off, this is a 2016 Chevy Express 3500 6.0L (L96) and 6L90E trans combo. It uses the E78 ECM and a mechanical fan (no fan trigger wires in harness). It's going in a 71 C10 with Vintage Air, Dakota Digital Gauges with OBD-II BIM controller, and the van's fuel pump in an aluminum tank. I have a new PRC aluminum radiator for an LS swap and dual Spal fans. I plan on running the fans off a trinary switch and an Entropy LS Swap fan controller since there isn't a fan trigger in my harness.

Easier Questions:
*Can you confirm that I do not need the A/C pressure sensor, or the A/C Relay Control from the ECM, or the A/C Request from the van Harness?
*I also have 6 wires that have "brake apply sensor" in the description that goes to a "brake position sensor" in the van. Can I delete these? I plan for the TCC Brake Signal to go to a relay for the brake switch, or I'll replace the 2 pin switch with a 4 pin switch.

More complicated Stuff:
*There is a dark blue wire described as "accessory wakeup serial data" that goes from the ECM to the trans, and the diagrams show it going to the BCM and Instrument panel. I'm planning on leaving the ECM to trans connection and deleting the rest of it. Is this okay, or does this need to go anywhere other than the trans, like the OBD-II port?
*There are other wires that go inside the van, but not to the ECM that I think I can delete. They are: "Serial Data Communication Enable", "CAN Bus high terminated serial data", and "CAN Bus low terminated serial data". The CAN Bus stuff I'm not sure about, but I do have the "High Speed GMLAN Serial Data" wires, both + and - going to the DLC (OBD-II port) pin 6 & 14. See below for DLC pin-out info.


My DLC (OBD-II) is shown to be like this for the van:
1 - Low Speed GMLAN Serial Data (I assume this is not needed, it goes to the BCM in the diagrams)
4&5 - Ground
6 - High Speed GMLAN Serial Data (+)
14 - High Speed GMLAN Serial Data (-)
16 - Battery Positive - 20A Fused from truck harness.

Any help is greatly appreciated. Let me know if I've left anything out that you might need to know to answer these questions.