Lighting headaches

[DeepWoods 1009]

I’ve recently been having an odd electrical issue with one of my trucks, A 923A2 cargo truck.
Periodically my running lights break lights and headlights will shut off and it seems as though they all turn back on after the switch or the head light relay cools dow.
I have changed both of the relays on the outer firewall under the hood, and no change! I’m not sure but I think there is a another relay buried under the dash panel somewhere, can any one confirm this.
I do use the truck for long term hauling sometimes and on occasion I will be driving at night when the lights stop working and it is getting more frustrating now that I have attempted to fix the problem.
Picture of the fleet.
A picture of the fleet.

 

[NDT]

The 3 lever light switch has a self resetting circuit breaker inside. You either have an intermittent short circuit, an overload, or the circuit breaker is shot requiring you to replace the entire switch.

 

[DeepWoods 1009]

The 3 lever light switch has a self resetting circuit breaker inside. You either have an intermittent short circuit, an overload, or the circuit breaker is shot requiring you to replace the entire switch.

The first time the lights stopped working was a couple of years ago, and at that time I had to replace the light switch because it completely died none of the lights worked at all!
I had gotten a use switch from a friend of mine which came out of his deuce and a half, and it was working fine for a few months then the lights started to go out intermittently and then come back on.
It sounds like from what you are saying that I will have to get another one? Do you know where or who sells new old stock?because I don’t want to get another used one . Pick your favorite surplus site and I’ll be on my way.
Thanks
Luke

 

[NDT]

The first time the lights stopped working was a couple of years ago, and at that time I had to replace the light switch because it completely died none of the lights worked at all!
I had gotten a use switch from a friend of mine which came out of his deuce and a half, and it was working fine for a few months then the lights started to go out intermittently and then come back on.
It sounds like from what you are saying that I will have to get another one? Do you know where or who sells new old stock?because I don’t want to get another used one . Pick your favorite surplus site and I’ll be on my way.
Thanks
Luke

Time out. Don't throw parts at a problem, that is a rookie move. Inspect the wiring stem to stern looking for bare wires touching chassis.