Help! Intermittent no start

[Horsman]

I will drive my C20 about 30 miles on a 90 degree day, park the truck and try to restart after five to ten minutes. Turn key and have complete silence. New starter, engine wire harness, NOS ignition switch. All these items were replaced before started having issue. Strange thing is it will do this randomly without any warning. If truck sits for about thirty minutes it will start.

Anybody run across this? Was wondering if the neutral start switch could have an intermittent issue. The column and switch seemed unusually hot tonight but might be normal..

Thanks in advance.