I just looked at a 1965 Mustang and the owner says it may be one of the first GT350s produced....#31. It had a Shelby badge on the driver's side fender down from the VIN tag and on the driver's door below the data tag....both stamped 31. It also had a GT350 emblem on the rear by the passenager side tail light. Here is the informatoin I could gather from the car: 5R09C174117 63A 3 26 14A 71 6 6 Passenger side rocker panel: 11 30A(8 or 6) 65 R Thank you very much for your help!
Disclaimer: I didnt read this, but it may be helpful? http://www.autotraderclassics.com/car-article/How+To+Spot+A+Clone-75457.xhtml