Good question m8! If your engine number falls after March 2002 it may have the revised jet fitted! but dont quote me on that! there's enough info on the site for you to investigate,but if i were you i would just get it done!
take it from me my car had only done 45000 and the guide failed im now having an engine transplant as we speak! and its all coming out of my own pocket :evil: :evil: :evil: