I think you make a very valid point about the plastic stripping in the radio tray posts. I have at least one that is very close to needing replacement. I think they are the same length as the 12M posts - i have some on order so hopefully they are!!!

As for rear wheel fitting. It's the same problem that all 12th cars have. They are made to run Jaco/CRC offset wheels. Where as Parma, TRC/GRP (flouro yellow) have the different offset. Personally, i just shim the axle - the same as people would with virtually every other car. I only use TRC and Parma wheels/tyres.