In our recent article about the somewhat mysterious Mustang Shooting Brake, we quoted sources from the book Intermeccanica, The Story of the Prancing Bull by Andrew McCredie, who implied that the project was conceived by the ad agency J. Walter Thompson. McCredie wrote, ”Cumberford and a fellow designer by the name of Barney Clark were approached by J. Walter Thompson to devise a way to get Ford’s attention, and the clever duo came up with a show stopper – a Mustang station wagon.”