Operator manual #A-5193 IPL 1 page 152.10KB Dated 7/8/70   Fits GT-14 Completing package requires 6-9612 54" blade   Also see the 6-4113 file for 42" blade   Although the 6th or last digit is not used you can subtract 5 from that number to determine the model year.   1970 Blade Dozer 54in model 6-4113 A-Frame 1970 serial numbers that have shown up for the 6-4113 647370 655328 655758 656686 656733 666011 1971 Blade Dozer 54i