 Working as a consultant firstly with Jack Griffith, then Frank Reisner in Turin, he designed the chassis for the Bob Cumberford shaped car the Intermeccanica Italia.Crosthwaite altered and improved the set up and suspension on the Lola T70 of New York-based racing driver John ‘Buck’ Fulp.Fulp won the Watkins Glen Sports Car Grand Prix and the Riverside 300 km in 1966.