Overdrive button wiring help

[disillusions]

I did a knob swap a while ago, and have my OD button rigged with a cable tie under the console; but obviously it can't stay that way. I wanted to put in a toggle-switch, but I read that there are 3 wires going to it instead of the usual 2; so does anyone know what this third wire does? Or even better, how do I connect it to the toggle?

 

[mrfister11]

red with white goes to TCU, red and green goes to cluster, other goes to fuse..

when switch is off it connects the cluster and fuse wire,, which turns light on. when it is connected to tcu.. obviously it takes power from light and puts it to TCU which engages OD. you need a switch that will connect one wire to one on one direction. then the other to the same power wire in the other.. i forget what type of switch that is called.. not a traditional on/off switch.. unless you dont care for the light then just use an on/off and connect the red with white to the L-R wire


single pull.. double throw