ARMY TM 9-2815-259-24 AIR FORCE TO 38G1-125-2 MARINE CORPS 09249A/09246A-24 5-80 FIGURE 5-77.  MEASURING ROD CENTER-TO-CENTER BORES (3)   Assemble the pistons and connecting rods per the following steps: NOTE If new piston and liner assembly is to be installed, leave piston inside liner.   Push piston out of liner bottom only far enough to install piston pin. (a) Lubricate piston pin (9, Figure 5-72), connecting rod piston pin bushing (10), and piston pin bore in piston (4) with clean engine oil. CAUTION Install pistons on same connecting rods as pistons were removed from.  Use new piston pin snap rings.  Failure to comply could result in excessive engine wear  or engine failure. (b) Assemble piston (4) and matching connecting rod.  Insure that the word “FRONT” on side of piston and side of connecting rod are facing same direction.. (c) Insert piston pin into piston pin bore in piston and through connecting rod piston pin bushing. (d) Install new snap rings (8) with sharp edge of ring facing away from piston pin.  Insure that snap rings are seated in grooves of piston pin bore.