where is this located on car

It is not located on the car. It was a credit card sized metal plate that was taped to the warranty booklet when the car was purchased new. The card was punched with information that would be helpful when servicing your car at the dealer. Items such as option codes and the VIN were punched into the card from the factory. The dealer then used special white plastic tape to put the original owners name on the plate also.
Most of the time the plates were thrown out once the warranty expired. However if you find the one for you car it can be a great source of documentation for your car.

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The protect-o-plate was not attached to car, but in a booklet usually in the glove box. The plate included the original purchasers name and was used for warranty service.