Actually the cars were built by a TAFE teacher from Sydney. Mark spent 6 months on the set building the cars. He has a string of credits to his name from earlier Mad Max films to The Great Gatsby. The Duesenberg in The Great Gatsby is actually an F150! He can't post info or photos until some time after the release of the movie but I've looked at his personal photo album from the shoot.
Natoli Panel Creations
Film cars:
Cinema Vehicles :: Natoli Panel Creations
PS. Mark said Charlize Theron kept pestering him, wanting to be introduced to his mate who was building the 250 GTO.