I read on one site how to install that thing. Would be instering to watch the semi assembly line process of installation. I think the guy had wrapped a large strap all the way around body and cranked down until screw holes lined up. But then again I remember rebuilding the brake booster on my big healey using the supplied o-ring to help flare out the leather cup seal, First time I hit brake pedal, it buckled the rod and locked brakes up. I tore it down straightened shaft then threw oring in trash. It was a one way working disaster. Later I read on somones site, that the oring body diameter was too large and didnt work. Gee really??? Nice to find out original factory parts dont fit. These parts wernt even current reproductions, but old stock replacements. Follow first instinct, is it right??? Naw cant be...Follow factory directions...OOPS! THATS WRONG!!!