Deezler, have you looked at what Tasdouille has done to his Mk III Jetta for his 79 mpg mileage run? He shielded the tires much lower. I like the Corvette style flap. Wiki Gurney flap and see what a little lip did for a rear spoiler wing.
http://ecomodder.com/forum/showthrea...15-a-4805.html