Thing is most of these laws regarding cossie converted cars etc already exist its just that it has been hard to enforce as traditionally the MoT man doesnt care if its radically altered as long as it pass's the safety aspect of MoT, where as if DVLA gets its full way then presenting a radically altered vehicle for MoT might be harder.

Thing is technically if you do a cossie conversion then you should go through IVA anyway as its a rebuilt/RAV anyway. Its just that people have been getting away with it so far.