Dee ihe na-aga n'ihu maka paragraf a - N'afọ 1974, Postlethwaite haziri ụgbọ ala ọhụrụ maka otu ahụ, Hesketh 308, nke dị njikere maka Silverstone International Trophy, nke Hunt meriri, na-eme ka ọ bụrụ onye mmeri mbụ ya na South African Grand Prix. Ụgbọala ahụ siri ike, na-ewere ọnọdụ nke atọ na Swedish Grand Prix, Austrian Grand Prix na United States Grand Prix
Ọ dị mma. N'afọ 1975, e rere ndị nke 308 nye Harry Stiller Racing, onye nyere Alan Jones nnukwu ihe nrite mbụ ya. Polar Caravans zụtakwara chassis Hesketh, ebe ndị ọrụ ọrụ gbanwere 308 maka Hunt. N'otu oge ahụ, Horsley na-etolite ịbụ onye njikwa otu egwuregwu dị mma ma nwee ikike na n'okpuru nduzi ya, ndị otu ahụ gara n'ihu.