Have you thrown together a model WITH the tow vehicle to look at airflow? Maybe you could fit in more interior space on the front if it's within the template. Of course you'd want to accomodate about 15* of yaw in the air flow as well.
I was imagining a boat hull type construction with longitudinal wood slats. That would look fantastic.
Another thing to think about would be integrating the wheel pods into the body. I was thinking you make the standard 40's style wheel and skirt, but then extrude it into the body. Kind of like this Topolino dragster I saw a couple years ago, but with skirts.
It would eliminate the aero uncertainty of the "tunnel" between wheel and body. Of course, you'd want to make a legitimate teardrop instead of this stylized mud guard.
