12 TRUCK BODIES; FORWARD-REVERSE TRANSMISSIONS FOR TRUCKS; DERRICK MOUNTING ATTACHMENTS FOR TRAUCKS TO PROVIDE A SWINGABLE AXIS OF PIVOT FOR THE DERRICKS FOR FACILITATION OF MOVEMENT OF THE DERRICK BETWEEN OPERATIVE AND STORED POSITIONS; A-FRAMES FOR TRUCKS FOR SUPPORT OF DERRICKS; TRUCKS AND TRUCK BODIES FOR MOUNTING DIGGING MACHINES, NAM-LIFT TYPE AERIAL WORK SUPPORTS, AND WINCHES; AND PARTS THEREOF