ZDriver.com - 280z reverse switch help!!

First of all, welcome to ZDriver.com. You'll find a bunch of helpful people here.

If you haven't already done so, be sure you download the factory service manual (FSM) for your specific car. You can get yours here (for free): XenonZcar.com S30 Reference

Those manuals are chock full of information for your cars and in many opinions, are better than the Haynes and Chiltons manuals. Almost every time I go into mine, I learn something new or understand something better. The answer to your question is definitely in the manual but ... I'll help you as well as I can anyway.

From the main harness as it exits the firewall into the engine bay, there should be a thin "tributary" cable branching off. It snakes itself down and back into the transmission tunnel where its connectors mate up with the transmission. There are a couple of diagrams in the FSM which nicely illustrate the cable routings and will even show you the connector types you should expect to see.

Good luck with your ride!