Starter clicks using the key, engine starts by jumpering the relay

Step by step how it works

Start relay coil/ electromagent AKA the two small push on terminals

1...NSS switch must be made which grounds the NSS wire, it connects to one push on relay coil terminal

2...Remaining relay push-on terminl is start wire, so key must be supplying power in start, that power must be coming through the bulkhead terminal, and must be comiing through the seat belt interlock if installed, and to the relay terminal, through the relay, and back to ground through the start switch

3....This pulls the relay in , closing the two contacts which causes the big "square" terminal to come alive, sending power to the starter solenoid.