While on vacation last week, I was passed by a pickup pulling a flat-bed trailer with a car on it. In front of the car was a half-circle airdam that went from the floor to just above hood-height. It looked like it would be fairly effective.
I'd definitely fair and skirt the wheels. Throw a half-circle on the front too. Do the doors swing out or down in the back? (swinging out would make boat-tailing simple)
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