3rd Brake Light CHMSL

[RobsZRinAR]

Hey gang,
I searched and found a couple of other threads on the subject but they haven't lead to my resolving the problem.
A Super-Trooper pulled me over last week just to inform me that my High Mount Stop Light was out. No ticket - just a friendly notice. '03 S-10 CC ZR5.
As I often have my 6 yr old grandson with me, I'd like to remain as safe as possible!
I pulled the lens (cracked - fixed with super glue), both bulbs were black. I thought "Ahh, sweet! Easy fix!" New bulbs didn't do it. No water was in the housing after several days of rain but, new lens is on order from LMC.
I found the relay CHMSL in the fuse block under the hood and replaced that. Still No-Go.
This morning, I crawled under the dash and checked the connections on the Brake Light Switch. No way to test it at the moment but, from what I gather from the other threads, this light is on its own circuit and relay. The switch should have no say in the matter, correct?
If I am right so far, I need to start looking for shorts or opens. Problem is - I can't find where the harness is coming from, even with a schematic. All connections at the light are nice and clean. Do I have to rip out the liner to trace these wires forwards?
Is there a 10A fuse somewhere that no manual is telling me about? Please advise if you have had this problem.

Thx, Rob

[ApproachMedium]

there should be a fuse for the 3rd brake light if it has its own relay. it should be under the hood keep looking. I dont have my truck here just yet to check but i swore i saw it. It should be buried by itself between some relays and not with other fuses