Wiring P/N switch for non-E trans

[AnimateMe]

I asked this question a couple days ago in someone else's thread in the Gen 3 section but didn't get a response so I thought I'd ask here. 2004 5.3l from an Avalanche in a swap with the stock P59 and harness but I've stripped out all the AT wires except VSS. I have the PCM pinout diagram and I want to know which PCM pin(s) do I wire to the switch? PRNDL A, B, C, P?? Does the pin supply the voltage or the ground? Lastly, should the switch be closed in P/N or in gear?

[blindsquirrel]

f-body P-N.png tahoe PRNDL.png

screenshot.30-03-2023 14.29.53.png

Except... if you look at a tune file for the F-body, it has PRNDL Equipped = None. So confuse!

[AnimateMe]

Thanks for those diagrams Squirrel, they answer my initial questions but trigger others. If I'm interpreting the diagrams correctly, I wire one side of my simple single pole P/N switch to C1 34 (PRNDL P) and the other to ground. P/N mode is triggered when switch is closed.

My swap is in a 69 Camaro and I'm using the stock Avalanche PCM & OS (12587603) which shows PRNDL enabled in stock form. And I've stripped out the Avalanche wiring harness to be stand-alone w/o AT as shown on LT1swap.com. I'd like to better understand how the stock PRNDL switch works. What do PRNDL A, B, & C do? Do I need to have a second switch ground any of them when the P/N switch is open and if so, which one(s)? Should I change the PRNDL to P/N only in the tune?
Camaro 12 initial SD w eng abuse off.hpt

[blindsquirrel]

Why not copy the F-body setup and see what happens?

But honestly, if you have to add wires back in, why not put it back like it should be? If you're already there and adding one wire, how much extra work would it be to add 3 more at the same time? Are you using a transmission that has the PRNDL switch on it, or is this something you're adding to a non-elec trans?

[AnimateMe]

Non-electric