Thank chaps.
Good suggestion about the top rail, possibly just have the number visible through a clear window in the bottom of the dash.
I agree, even if it was stamped or etched into the chassis it is easy to cut out and replace. But I believe Mr IVA has issues with this plate not being 'secured'. I see no issues with any method as long as it doesnt fall off! As you say if you want to change it, you can.