I had installed a car radio/cassette player in our previous 13' Scamp in the farthest corner of the overhead cabinet over the table (almost unusable space) with speakers mounted facing downward in each corner of the cabinet. I used one of those radio wire antennas taped inside the same cabinet (worked well).
In our present 13' Scamp I had installed a wire shelf over the dinette/bed and just take our home "boom box" style X-M radio and set it on the shelf. The faceplate goes in our tow vehicle for music on the road, in the boom box for music in the Scamp or in our home (works on 110 volt or 12 volts). I did find that the fiberglass/reflective insulation blocks the signal, so the antenna had to be placed within our escape
hatch between the screen and the cover (closed or open works). There is also input jacks on the boom box to be able to plug in whatever music source you would like. I feel this set-up works better for us, as most of the time we camp off the grid and where normal radio signals are either very scarce or not at all. X-M works all the time for us.
Dave & Paula