I decided to just add a couple feature lines in the wings, to add a little motion to it, and the boss/counter bore for the motor meter mounting bolt, and do the rest of the detail work by hand. I need to see it on the car to determine just how much detail I want in it. I'm going to cut it tomorrow, or early next week.
The larger the end mill the less detailed the feature lines will be. I don't really want a lot, just a subtle hint; and I'll blend the edges a bit by hand, after I see it cut.