74 Duster won't start

Sit down, buckle the seat belt, and see what happens. '74s had the accursed seat belt interlock that wouldn't let the engine crank without buckling up first. There is a sensor on the seat bottom springs. Unplug them and that should take care of the problem if that's it. I unplugged the sensors on my '74 Charger before I drove it off the dealer's lot.