Neutral Safety / PNP switch ??

[yossarian19]

I've searched a bit and am not finding the info I am looking for.
What I think I remember reading is that the PNP switch has three functions. One, reverse lights. Two, keeps engine from starting in anything but neutral or park. Three, adjusts idle speed by 100 rpm or so depending on if you are in neutral or drive.
The GM rep at SEMA said the PNP wasn't really necessary for a swap.

The harness I have uses 2 connectors for the PNP switch. Both are basically toast.

So at this point, do I get rid of the PNP wiring? If so, can I do anything to get my 100 rpm idle increase while in drive?

What else am I missing?