which is the reverse wire on the taillight manifold?
most of the time on trans,some up beside mastercylender.
You'll need a wiring diagram for this. Not sure off the top of my head which one it is anymore. Test the wires using a test light and the one that doesn't have power when vehicle is in park, should be the one. Have someone step in and carefully put it in reverse with foot on brake and check the wire to see if it has power at that point.
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