Model: 4044M, 4044R, 4052M, 4052R, 4066M, 4066R, 4052M Heavy Duty, 4066M Heavy Duty Tractors. Which Manual do I need for my John Deere 4044M, 4044R, 4052M, 4052R, 4066M, 4066R, 4052M Heavy Duty, 4066M Heavy Duty Tractors?.