TM 10-3930-659-20 14-2. CAB DOOR REPLACEMENT (Con't). b. INSTALLATION 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. 1. Position cab door (1) on cab (3) and loosely install two screws (4) on upper hinge (2) and cab. 2. Loosely install two screws (5) on lower hinge (6) and cab (3). 3. Close cab door (1) and ensure that latch properly engages.  Tighten four screws (4 and 5). FOLLOW-ON TASKS: • Close cab fresh air filter door (see TM 10-3930-659-10). 14-5