I'm on my third year with my Lil Wil on the S10. Ran the coax over the roof, down between the box and the rear of the cab. I drilled through about 6" off the floor and 8" from the side of the body. Wrapped the coax with numerous layers of duct tape until it was a snug fit. Caulked it from the inside with clear silicone and sprayed the outside 3 or 4 times with Clear Flex Seal. Now my S10 goes on water AND has a radio!! I figure I just need to spray it every couple years, and you can't really see the clear rubber between the cab and bed.
I also use black flex seal for all my outside coax fittings. Haven't had a problem yet. Even the main solder joints for my connection to the copper J-Pole.
Don't get me wrong, I drill holes in brand new truck cabs for light bars, emergency LED lighting, sirens and multiple antennas several times a week. That just smells like work to me if I have to do it at home on my own trucks haha.
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