Tape over orange coroplas..
I didn't want the rear skirt to budge out into the air stream, or rub the tire. So, I made it super short. (5.25").
I didn't want the front wheel to rub when turning and it ended up being 4" tall..
Not so sure that I'm going to see any better MPG, but maybe all the mini-stuff will add up to something..?.
Got a 200 mile trip coming up in a couple of weeks!