My CB is loosely sitting on top of the battery (removed the rubber strap holding battery) . The AM/FM radio is vertical behind the battery.
The CB can easily fit behind the battery leaving the AM/FM in its spot. It may be helpful to cut away some of the plastic in that spot. Thanks for the suggestion, It was installed by someone else, and I haven't really messed with changing it,,,, it seems to be fine where it is,,, I may have misused the term "loosely", as it isn't moving anywhere from where it sits once the seat is installed.