I picked up a cheap Uniden "mini" CB and have it mounted on the driver side sport bar with large hose clamps. Its not easy to steal but if it does get stolen Im out only $30 and my jeep wont get dammaged if they do rip it out.
"But it does me no injury for my neighbour to say there are twenty gods, or no god. It neither picks my pocket nor breaks my leg." - Thomas Jefferson, Notes on the State of Virginia, 1782
Arguing with a truck driver is like wrestling with a pig in mud, eventually you realize the pig enjoys it.
Another option....and this is what I do. I use the handheld Cobra 38WXST radio, and connect that to a full size 4' Firestick antenna. Gives me pretty decent transmission, plus the ability to take the CB with me if I have to get out of the Jeep, for instance to scope out what's ahead on the trail or to help someone, and remain in communication with the group. When I don't need the CB I remove the radio and antenna from the Jeep.
I put mine in the center console, mounted on the inside up against the driver's side. It eats up space in there, obviously, but it was mainly filled with junk anyway. Now it forces me not to just dump everything in there. Drilled a small hole for the power and antenna wires near the bottom and ran the wires under my seat. Now I just keep that console locked until I need something from it, or I need it on. On the plus side I think it makes it sound a little louder since the sound bounces around in there before coming up the top.
I use the Cobra 38WXST handheld CB. Reception is fine. It's transmission strength that lacks in comparison to the big units, but if you hook it up to a well tuned 4' Firestick, it does the job. I don't have any problems with anyone else in the group hearing me on the trails.