If you have a truck bed tool box, you can easily fashion a bracket for free out of a chunk of angle from the hardware store. Put a Firestick or similar on it when you want it, unscrew the antenna and toss it under the back seat backrest when your not needing it. You can always make it a temp install and run the cable out the back door to the toolbox, when done unscrew the cable and roll it up and tuck it under the back seat backrest as well.
This would be my most favorite CB for myself or to reccomend. You can take it to a local CB shop and get "peaked and tuned" and it becomes a VERY respectable radio, and it has the coveted RF gain adjustment. So far as I know, this is the only compact radio that is capable of being peaked and tuned. And very few will have the RF gain knob.... and you want that! My personal opinion is that there is no better compact CB on the market, especially once you spend a few nickles and get the thing tuned along with a decent quality coax cable, connectors of decent quality and a decent antenna. You will fall in love with it and be shocked at how great a compact can be.
Uniden Pro520XL