Wire a nutral safety switch 3 prong in a 67a body

Just looking for insight on how to wire a nutral safety switch 3 prong In a 67 ...not original trans....i do not have the wiring harness...thanks
The center pin grounds when in park or neutral.
One wire from that pin attached to your starter relay ground terminal should do it. (Terminal 2 is the one to connect to)

That terminal on the relay has to be grounded for the starter to activate.
The center pin on the trans switch does that in park or neutral.

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