Neutral Safety Switch???

[FLYNAVY30]

Im using a painless harness on my '72 C20 that Im swapping a carb'd LS1 4L60E into. The thick purple wire going to the ignition switch has a break in it for the neutral safety switch but no amplifying information on how to wire it.

I realize the intent, but did these trucks come with a NSS from the factory? If they did, Id like to know how to properly wire it, if not, Ill just connect the wire and bypass the switch.

Thanks for the help!