OK I will try to get heater to do the videos the plan it will be a 2 part mold that way you can do all type of fannies things with it maybe the tiles you use in the kitchen lay in the top inlays of what ever in the side.
I have gone 91/4"/57.785cm wide . It leaves room for a flat tire. small off set 4 wheels. Had to round wheel wells to me it look bad if flat and a lot stronger if a tire blow out. I want a place if i did French teardrop light I did the side walls a full 3.5"/8.89cm to fell in side wall of trailer not as tiny it a full 30"/76.2cm long
You can make what ever side you want the buck will look like finish f........./part. If you want try some wood molding on top sides it you want resets on the side just use a router and cut some groves
I cut the out side outshap out of 3/8"/0.9525 mdf then
then glue to some 5/8" mdf that covered the whole shape that will be the run out on the mold

then cut last piece the back out of 5/8 mdf 1/8 to 3/4 biger that will be some of your taper.
It is not the return ON my investment that I am concerned about; it is the return OF my investment