As Sven said, that rear wheel can help or hurt your economy. If you look close at the first Zoleco pic, he has rods set up to curve from the side of the vehicle to the rear wheel. From the wheel, it goes up and back at an angle to meet the rest of the body. That's one way of fairing the wheel.
If you could do a reasonable pic of the dimensions of everything, I could draw something up that might work.
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