Owning and having owned numerous front number and builders plates....The number 10 plate was legit. I personally handled that plate a few months ago. The mounting stud was cut down and the stampings were removed in the process. I like most plate collectors like my plates original but, up until say 20 years ago that wasnt the case. Many plate collectors cleaned and flattened (for display purposes)their plates. To me (my opinion) it seems that when number plates surface, more than not they are cleaned however, builders plates seem to be a 50/50 split. This opinion is based on what I have accumulated over the last 20 years.