justpassintime, I wanted to use sheet metal, but I couldn't find any cheaper than $1 per square foot. I tried to find a salvage box truck that I could cut from, but never thought of cutting it from a car in the junkyard! Looks nice.
My materials were technically $0 too, but I had to buy the sheet metal screws, washers, and duct tape since I was out at home.
Preliminary results for the grill block and wheel skirts: +2 mpg on the highway: New high - 47.2 mpg today!
Grill block:
