Since I completed the hover truck and I still had some free time, I decided to make a test build of the structures. This picture show the results. They are printed at a scale of 39.4% (to play with cm as inches.)
The platforms are designed to be glued to foamboard but at this scale, a piece of cardboard had just the perfect thickness to be used instead. Therefore, I did not have to make any adaptations to the original pieces.
Here is a final picture with the hover truck for scale comparison.