Drawing is awesome.
Here are the parts not understanding.
1) I didnt find a single thread explaining that wiring until I searched on some keywords you provided on pinout of the OEM NSS. So Im guessing most people dont do it this way - they just use a column/floor shift with a 2 wire setup that prevents the starter from cranking ?
I think a lot of people either don't use a neutral safety switch or just use the one originally on the column.
2) How did you work out that was the way to wire it ? Eg Having the ignition switch going to Pin12 of the range sensor and that that would work ? Just experience and reading schematics and understanding circuitry better ?
I got the info from the factory service manual wiring diagrams. And yes, it does help if you know how to read a schematic, but I can try and walk you through it. Wiring isn't a lot of peoples strong point that's for sure!
eg I was searching on Pin #34 as that was what was registered at LT1swap.
"Transmission Range Switch Signal P (A/T) PCM can be programmed to accept a SINGLE WIRE park/neutral signal on this PIN, if no trans mounted range sensor is present" <== but guessing this is if your using an aftermarket shifter with NSS ?
This is for the info the computer uses and not for the other functions of the transmission range sensor. LT1swap only gives you the wiring needed to make the engine run. Back up lights and NSS functions are not included in his site because it would overwhelm most people.
So - just not sure how you worked that out - except for being just clever
Read for 4 hours on this. Found nothing.
3) Not clear on how you fuse every wire on each pin of the relay. Physically how is that done.
There are a couple ways to fuse the relay, either inline fuses or in a fuse block. you would need to figure out where you are going to put the relay, then mount the fuses close to that. Where is your fuse block for the engine harness located? You could just put it in the same location to make it easier.
Thx nova/e015475all ....... / none of this would get done without learning from you lot.