Is it the origional backup switch, or a nuetral saftey switch?
Assuming that you've got a console and its out of the way, or at least the indicator plate is removed. Either back your car up to the garage door or close it if the car's in it. Turn ignition to run and slide the shifter back to reverse and a bit past while looking into the rearview mirror. See if you lights come on at all. If so, you'll have to manipulate the tang on the shifter to a new position that correlates to the reverse lights working. But first check that there is power to the leads that go to the switch dependent on which switch you have.
Brandon J. licence 1NASTY67
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