aesculus
Still Trying to Figure This All Out
A bit off topic but have you considered offering a set of victory stickers? These would be applied to the car (like the back bumper or window) whenever someone dusted a certain make of car like Porsche, Ferrari, Maserati etc. You could make them a single color (black and white), fairly small and simple. Just the basic logo.
These would be akin to what pilots put on their aircraft after each successful encounter.
These would be akin to what pilots put on their aircraft after each successful encounter.