If you haven't replaced the existing bulbs with LEDs I would
recommend it! I replaced mine a few years ago with inexpensive bulbs from Amazon that fit into the existing ceiling fixtures.
When I removed a fixture to figure out how I wanted to install the recessed lights I saw pretty bad heat damage to the ceiling from the old bulbs.
So, anyway, I have cut some wooden bases in which to mount the lights. The existing ceiling is thin plywood and the lights require a thicker mount in order to be stable. I plan to cut a large enough hole in the ceiling styrofoam to allow an air gap around the light. The hole they cut just to mount this surface mount light is pretty big, so I don't think it will be a problem.
Running down the middle of the ceiling is a plastic channel that contains the 12v wiring. To avoid having to cut into it more than it is already cut up, I am going to mount the new lights to off-center. This will actually center them into the living area, as the cabinets on the kitchen side are deeper than the ones on the couch side, so off-center of the trailer is actually center of the living area. I also bought some automotive switches, that I will wire in so that each light can be individually powered.
The lights are really thin, so this should be a great improvement in height, and also update the look.
I haven't decided if I want to make a fancier base. Maybe something mid-century modern
The trailer is so small, I have to watch out for visual clutter, so small and square and white and unobtrusive might be the best option.
So, what do you think?