Some rental companies are being very slack in this regard. This happened to other visitors recently, but they were given only a warning and then had the new plates replaced by the rental company the next day. There is a little plastic envelope on the top left hand corner of your windshield showing the info you need for legal operation of the vehicle. It is always a good idea to check this before driving off the rental lot. Enjoy the rest of your trip with your new plates!
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