Re: Registration numbers
I used an eraser. They can be found at any paint supply store fo around $20.00. It looks like a big round pencil eraser with a threaded stud sticking out of the middle. It's used by body shops to remove pin stripes and emblem adhesive tape. There is a pneumatic tool for it but it works just as well in a 3/8 drill. Get it spinning and literally erase the vinyl off. It may leave some of the adhesive when you're done but a mild solvent will clean it right up.
A word of caution: It generates a great deal of heat (it is rubber spinning at speed against a surface) so dont hang out in one spot very long or you could pontentially damage the finish underneath the letters. It is the easiest and least time consuming method I know to do it.
