TM 10-3930-659-20 17-12.    FORKS REPLACEMENT (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. NOTE Note position of left and right forks to aid during Installation. 7. Remove  bar  (12)  halfway  from  carriage  assembly  (1)  to  free  left  fork  (2).    Remove  left  fork  from  carriage assembly (1). 8. Remove lifting device from left fork (2). TA707641 17-41