For 1971 Mercury Cougars and Ford Mustangs with the 429CJ engine. This is a Pitts manufactured pulley and clutch assembly with a pulley diameter of 5-5/16", a clutch diameter of 5-5/16", and an overall thickness of 1-3/8 inches.
Ford part # C9AA-2981-E1, may also have part # C9AA-2981-E2.