The hinge is a standard stainless steel marine VHF antenna mount ($35, West Marine, A2O in Clarksville, IN)with a 24" extension pipe ($25). I can elaborate if needed. I'm a little short on time right now.
At the top of the extension pipe, I cut off the threaded part (about 1").
I drilled and tapped, eight 10-32 stainless steel setscrews (Home Depot) to hold the PL-259 connector.
The tricky part is that you have to fish the Mini-8 coax through the pipe, then solder the end on.
I used the Predator PL-259 base ($20).
I damaged my first PL-259 connector by putting the setscrews too tight, and I crushed the predator inner insulator by screwing it too tight at first.
I used a large hole saw to get through the bed liner. I buffed off the paint where the hinge mounted. I used SS sheet metal screws to mount the hinge.
I put c-o-pper paste (never-seize) between the hinge and the bed to prevent rust and help with a good ground. I used the c-o-pper paste at all ground connections.
I used 1" c-o-pper braided tubing (~$1-$2 / ft) for the grounding. I used a hose clamp to land the c-o-pper braid to the extension pipe. the c-o-pper braid is smashed between the hinge and bed, and continues to the frame, and cab. I used #8 TEK screws and c-o-pper paste to land the grounds underneath.
The pipe makes the antenna tune a little long, so a little extra cutting of the whip is needed. The Wilson 2000 works well on it too. The long tune situation kept me from being able to use an Everhardt Tiger SOTT-5 antenna because it wouldn't tune short enough.
