RM Auctions expects an eight-figure bid for this extremely rare Ford GT40 prototype that will go under the hammer at its Monterey sale in August. One of just four roadsters built by the factory in the GT40's early days, there's every chance this will set an auction record for the model. Finding any surviving GT40 is rare, but this one is extra unique as it sports bodywork not found on the coupes, with a different midsection as well as unique front and rear ends.

The Ford factory and Shelby American both used this example as a demonstrator and, unusually for a factory prototype, has not seen any significant modifications made to it. Chassis GT/108 is ready to run after two decades in single ownership, prior to which Ken Miles, Jim Clark and Carroll Shelby all took turns test driving the car for Shelby American. The Ford GT40 roadster will cross the auction block over the weekend of August 15 and 16.