Maybe I didn't understand something but I thought you said that quzahs didn't recognise between numbers and letters. If I understand his code, it is based on the spaces. But I can't use spaces to recognise because when I get the plate it could have mistakes in the spaces and sais that there is a space where there isn't.
For example, it sais that the plate in the picture is 111 1 AAA, so we have one space more than in the pattern that is 1111 AAA, so I can't use the spaces for recognison.
What a do is : I get 111 1 AAA, I make it become 1111AAA and compare it with the pattern that is in this case 1111AAA (whithout spaces).
Maybe I'm explainig something that you already undesrtand, but I re-appologise for my very very bad english, so maybe I'm confused.