Fitz, what are the small squires near the corners of the front and rear bumpers?
Roundhouse nailed it.
Those are the Military blackout lights.
When turned on they give out just enough light that other trucks in a convoy can see you and hopefully the enemy doesn't.
When you hit 1 switch on the dash all of the civilian "service" lights ( headlights, tailights, brake lights, directionals, etc) and the horn are disabled.
Turn the blackout lights on and your good to go.