What is on the title? Most 1950 models were titled by engine number. The tag you show was a common replacement for lost tags or when a service cab was installed. I would keep it for the nostalgia of it. If you don't like it, you can install a reproduction plate. Manufacturers did not use chassis or VIN numbers until 1954. The 17 digit VIN as we have it now did not become law until vehicles built after 1981. If you are concerned about the regulations in your state, get on the department of vehicles and titling in your state. I would not ask an enforcement officer, because they usually don't know. If you live in CT, they are one of the more difficult states.