When I had my American car, I used to carry around a printout of a certain section of the UK registration plate legislation, with a letter drafted by a Mustang owner who was also a solicitor. The letter explained the legislation, in polite but simple terms, and was supposed to help 'get out of a fine' if stopped by the police.
As I sold my Mustang many moons ago, I no longer have either; however, if I recall correctly, the gist of it (and given this was for cars) was that there is an exemption of the vehicle was never designed to have a front plate. Obviously cars that are Euro compliant are required by law to be be built with this in mind but cars from the USA were different. I never had to use it but quite a few owners did and either the officer was 'blinded by solicitor' speak, or simply couldn't be bothered to read the document, so ended up letting the chaps go without a fine.
Whatever the case, I raise this point because I would question whether the police would look at the M3W, see that it was designed to wear a front plate and therefore fine you accordingly if you were without?
