Converted 74 Duster to auomatic on the floor, and now won't start. HELP!!?

You can't put the connector on backwards. Or to put it another way, if you put it on backwards, it would still work. The NSS is the center pin, the backup lamps are the two outer pins.

I think you may have saved the day!! If the NSS is the center pin on the steering column plug, that would explain why my car starts in gear. That particular barrel connector pulled free out of the steering column plug and had been rewired with a different connector, and I couldn't figure out where that wire was suppose to go. I can't wait to get home and rewire a new barrel connector and see if that works. Thank you very much!!