I have smaller letters, misspaced, totally illegal plates but also have fully legal plates which I put in the boot when going for an Mot. I show them to the tester & he is happy they are in the car as what I do when the car leaves the garage is not their responsibility. Unless the police are sitting at the garage door when I leave there is no come back on them. Granted, not all testers may not have this attitude, but saves a lot of faffing about. Worth asking.