Bad Neutral Safety Switch??

So i got a 2000 Silverado 5.3L. When it's super cold sometimes it won't start. Like it's got battery juice but acts as if it's not in neutral or park to start. The other day it was -30C, had it plugged in overnight, ( block heater and battery blanket ) and started great . Drove to work, plugged in for 10 hours , wouldn't start, hitched a ride home left it plugged in. Came to work the next day, still nothing . Said F it i'll just get it towed . Unplugged it it sat there for 10 hrs in -30C for my shift , for whatever reason tried it at end of my shift right before the tow, fired right up!!

Any insight on this!? Seems like a ground or NSS?? Any input appreciated!

4L60E transmission?

A quick google search suggests that neutral safety switch issues aren't uncommon, and also that the switch isn't expensive. I'd just replace it. There are some videos on youtube that turn up in the search ... watch them.

I believe it is the 4L60E. OK thanks for the reply I'll do some more research!