If you're in need of mounting an auxiliary antenna on your Duramax, the options are limited. Sure, you could get one of those magnetic or suction cup mounts then drape the cable through your door jamb. Or you could drill a hole in your roof (please don't), or maybe you've got a headache rack you could weld a mount to, but then you'll still need to figure out how to run the cable into the cab. Fortunately, there is a better way! Bulletproof Diesel has this great option that utilizes your factory third brake light to mount an antenna and it affords a convenient method for routing the cable through the 3rd brake light at the back of the cab.