TM 10-3930-659-20 22-8. PREPARATION OF EQUIPMENT FOR AIR SHIPMENT (Con’t). WARNING Use  extreme  caution  when  handling  heavy  parts.    Lifting  device  is  required when parts weigh over 50 lb (23 kg) for a single person lift, over 100 lb (45 kg) for  a  two  person  lift,  and  over  150  lb  (68  kg)  for  a  three  or  more  person  lift. Keep clear of heavy parts supported only by lifting device.  Failure to follow this warning may cause serious Injury or death to personnel. 3. Using on-board crane, lift and position upper cab (14) over lower cab (8). 4. Align four comer post joints (15) of upper cab (14) with corner post joints of lower cab (8). 5. Install eight washers (16) and screws (17) in four corner post joints (15).  Torque screws to 500 lb.-ft.  (678 N.m). 6. Install 22 screws (18) In upper cab (14). 7. Install latch rod (12) in catch (13). TA706790 22-10