My 300D has a University of Virginia frame on the front license plate, from the previous owner (it was originally on the rear LP). The oen on the rear is for a shop in San Jose called Coast Fuel Injection. It was just one I had laying around.
I want to get one that says "You're just jealous 'cause the voices talk to me" to replace the one on the rear of the Benz, and maybe get one that says something like "My other car is a truck" for the front.
For my F-250, I have the original dealer frame on the back (Jim Burke Ford, Bakersfield) and a CFI plate on the front. I hope to eventually replace that with "My other diesel is a Benz"