Can anyone Identify this MOPAR thermometer. Where does it mount?

These kind of accessories were sold at places like car washes and mom and pop auto parts stores in the 70s. Probably hanging right next to all the compasses people bought that got lost all the time. Probably less than 10 bucks unbranded from the same manufacturer, but the ones labeled with a make like the Mopar and Olds ones have to be worth some coin.