also grounding the wire to an external source like that is a great way for corosion to start...even though it has a grommit.. condensation is a big player with installs like that... and thats a spot where you dont want it.. even runnin a dedicated ground wire into the cab and attaching it the the X frame on the cab side of the roof might be a better idea then screwing the ring terminal or spade term. to the moutning screw

why do they call them clearence lights?

 

the reason i think there called clearence lightsand correct me if im wrong but its cuz they can help u see how close you are to say an overpass i know wen i used to drive truck in the cab there was a switch to flash them to help you see how close you are. if i was ever that close that i wasent shure it get out and look but there are some who are too lasy to lol

 

Where exactly is that plug underneath the dash???

 

well that makes sense!