Hello, I am rebuilding a 74 318 Duster and I have a 74 and a 73 wiring schematics. I have bypassed the seatbelt interlock by splicing both yellow leads to the interlock relay together. I understand how the neutral safety switch works and that the center pole connects to the starter relay and one outer pole is for 12+ From the fuse block via the firewall connectors and the other outer pole is for backup lights that routes thru the firewall connector and on into the rear body harness. My question is where do the 3 wires that come from the neutral safety switch connect to the main engine harness. On my car there is a 3 pin connector that is pigtailed off the wiper firewall connector. It does not jibe with either schematic but neither schematic shows the seatbelt interlock and the car definitely had the system. There is also a single lead out of this firewall connector that's for the washer pump. The car is in the process of being reassembled and not quite ready to plug it all back in and connect battery power just yet. I plan to trace the other side of the firewall connector to see where these 3 leads go once the are in the cabin. I am also wondering what the symbol I have circled in blue on this schematic is supposed to represent? Any thoughts?