If you watch the film you'll notice a lot of Saleen vehicles running around. Not only are these "extra cars" from the Saleen family of products, they're actually the Saleen family's personal vehicles. The white GT is Steve's personal vehicle. The orange Saleen S302 PJ, designed to pay homage to Parnelli Jones, is actually Parnelli Jones' personal S302.
If you look in the background you'll see a bright pink Mustang, which belongs to Steve's daughter and is custom-painted Molly Pop Pink. We had a long conversation with Molly about her cars and we were not only impressed with her knowledge, but also with her ability to chat through much of the long filming process. You don't want to know how much that thing costs to repaint.