fig2 a cylinder marking convention 15 and a sleeve marking convention 17 are shown as seen from the cylinder marking convention 15 each cylinder is marked to show two components of information which include the outside diameter of the cylinder and a number that distinguishes the cylinder from other cylinders of the same diameter as seen from the sleeve marking convention 17 each sleeve is marked with four components of information the first two represent the cylinder to which the sleeve is associated the third number represents the outside diameter of the sleeve and the final number distinguishes the sleeve from other sleeves of the same diameter the letters u201c c u201d and u201c s u201d or another appropriate indicia may precede the diameters to distinguish a cylinder diameter from a sleeve diameter unless the order of presentation is a part of the convention while the above marking convention is exemplary it is to be considered only one of many within the conceptual framework of the present invention in fact any convention which relates the unique codes symbols or signatures of a discreet cylinder and a discreet sleeve having a relationship by virtue of customization of the cylinder and sleeve as a unit is comprehended by this invention by way of illustration a convention of the form xxxyyy where xxx is any sequence.