Neutral safety switch 89YJ

Been working on the YJ for the past 3 weeks now. Started with a weber conversion that went well, progressed to a nutter bypass that put the computer to sleep permanently, replaced the radiator and did a cooling systems R&R. Replaced the few remaining vacumn lines with all new hoses. Painted the front bumper and added two new tow hooks, replaced the steering stablizer, new EGR, new temp controlled vacumn switch, it all works great, jeep idles like a champ.
The only little nagging thing left is that it won't go anywhere, put it in R, D or L and it DIES. We finally traced it to the neutral safety switch which on this tranny is located right above the tranny pan on the drivers side. Found it by disconnecting the linkage and it would stall, not stall really but 'shut off'. We jumped the plug in the engine compartment and now it runs fine but starts in any gear. What we are curious about is HOW it can do this. I know others have had problems with NSS's on XJ's but that usually a 'wont start' thing, not a starts and won't run problem. The chiltons as usual is useless and the only thing that provided was the fireorder for the snap on diag machine.
Gosh I hate automatics.....

I'll take a guess.....

It sounds like you wired the power to your ignition through the NSS, so any time you shift out of P/N, you kill the power to it.

The ign. should get power from the "run" position on the ignition switch, the wire goes from the "start" position on the ign. switch to the starter relay should go through the NSS.

HTH