3D-ing the underbody does not mean making the wheels 3D. It means actually going under there and making every separate box for all of the hanging equipment, and placing both 3D axles and wheels, and trucks. The underbody can be part of the side texture, just as long as all the dark areas around the equipment is transparent.
I believe there's a misunderstanding. I could care less about 3D-ing the underbody or the wheels, but it looks like they're going to add a bit more detail to the axles which is a great thing.
What I'm concerned about is the PROPORTION between the car structure itself and everything else below that point. From the given visuals, it looks like the R46 has the same problem as the R160, the car structure will not align correctly with the platform. The underbody seems too small height wise, and as a result, the doors will sink below the platform. There is a fix to this if you modify the texture and make the underbody a bit larger to avoid this problem, however, with the introduction of a more detailed axle, I don't know how easy it will be to fix it now.
See, this is why I encourage you to get into developing, because everything you just said was redundant.
If the underbody had been 3D, like I just said, then its proportions would have been just right. The reason for that is because the wheels are needed to be visible, so the vertices of the faces that are textures are applied to are raised a bit, creating the small underbody problem(which in actuality, raises the entire side texture which is never really separated from the underbody, and makes the doors
higher than the platform), which is another reason why they should be 3D objects(I did the same thing with the first version of the R62, so I should know).
Gong Gahou is right though. I just skimmed through my texture library for a moment, and noticed the small differences in the truck textures. but that is very small, and I can swap out the R62 truck textures with that of the other SMEEs at any time, depending on the model(since the entire truck model is made primarily out of textures). I'll see about converting them sometime.
BStyles