I've pulled the latest belly pan and wheel pant assembly off of Dark Aero. Looking at the belly pan where I painted it white, there wasn't any indication of any streaks in the recessed areas from the dirt flow modeling during the last run in the rain. I guess this tells me no turbulent air was gitting up into the recessed area.
The wheel pant assembly was taking a pretty good beating from the road vibrations. All of my steel pop rivets were loose, some had fallen out. Two screws had snapped off while two more had backed out some. I will have to rethink this setup if I go back in this direction. I will eventually have something that will have the "1WD" on each side of the wheel assembly again.
After taking the wheel pant off, the wheel had a good covering of fine powdered dust similar to brake dust on the outer part of the rim which I guess it sucked up from the road and the rotating force of the wheel deposited it on the rim...rather interesting. No grease marks which tells me that my felt liners are doing their job of keeping the grease in the hub. I did have to add a few pumps of grease into the hub.
I'm going back to a belly pan similar to my original setup and see what I can improve. I guess I'm down to scraps of Coroplast now...