Oh, and I'd just like to add, the two kits I mentioned above are the more affordable ones. They both have fiberglass bodies. If you want the best of the best, you go with the Kirkham kit:
http://www.kirkhammotorsports.com/products/427-style
^ Theirs is hand-shaped aluminum, just like the original, and probably the closest to a real brand new Shelby you'll get without a time machine. DEFINITELY not cheap, though:
http://www.kirkhammotorsports.com/pricehome/price.html
EDIT: Here's the article I was looking for:
http://www.insideline.com/ford/shel...-build-50-special-edition-csx8000-cobras.html
The aluminum version's body is supplied by Kirkham. So yeah. And these are considered real Shelby Cobras, though the purists tend to look down on the fiberglass ones. These "new models" are considered the "continuations."