I have to ask the obvious question, which is why not fiberglass? Believe it or not, it has some advantages over metal, and the availablity of more styles, and cost should make it more desirable to you.

I have a lot of experience with Corvette work, motorcycle bodies, racecar fiberglass, streetrods, prototyping, and some minor manufacturing, and I can tell you that there are compromises and limitations with either 'glass, or steel.