My 92 defender recently failed its MOT. I have decided not worth spending the money on getting it through the MOT and wish just to use it on my farm and travelling less than 1.5km on public roads between the land I own. How do I notify the authorities - I understand a V112 form is required next time I would normally tax the vehicle (presently it is taxed ). But is there a form I need to fill in now - or in the very unlikely situation I get stopped by plod do I just tell them the vehicle is for agri use? It would also be good if I am able to claim back rest of tax???