I've decided I'm going to make the fairings in two stages: first, I'll cut the drain pan in half, trim to fit, then connect where the middle piece of trim is, so the flat part of the fairing will be diagonal, facing rearward. This is a means to an end, not an end in itself, because the second stage will connect to that and extend past the rear bumper, making the bottom part of the partial boat tail. I think it'll look pretty cool, very unique at least, and it will definitely smooth the airflow past the bumper, so the only trick will be getting it to release cleanly. I think if I can fashion the edge into a trip device (a la Chevy Volt), that shouldn't be an issue. It'll also look retrofuturistic, which isn't even a word.