TM 55-1680-358-12&P NOTE Floor    patches    will    be    handled    on    an individual basis from aircraft to aircraft. (1)    If  floor  repair  patches  are  present,  they could   cause   interference   to   Helicopter   Internal   Cargo Handling   System   installation.      Modification   to   the   rail/ roller  assemblies  (1  through  6,  Figure  3-2)  will  then  be necessary.    Refer  to  paragraph  2-8b.(6)(i)  for  floor  patch modifications,  if  required,  and  then  complete  installation as follows: NOTE 10k tiedown fitting assemblies are located at    stations    240.000,    320.000,    400.000 and 481.780 on both sides of the aircraft. (2)    Remove  eight  10k  rings  by  unscrewing from fitting assemblies (Figure 2-3). (3)      The   four   screws   securing   each   10k tiedown fitting assembly (Figure 2-3) should be removed. Remove   one   of   the   inboard   screws   holding   the   10k tiedown  fitting  assembly.    Install  one  of  the  two  special bolts  (41,  Figure  3-2)  and  flat  washer  (40)  to  keep  the tiedown adapter aligned with holes. (4)    Remove  the  remaining  screws  holding the 10k tiedown fitting assembly.  Stow the 10k rings and screws in a secure place aboard the aircraft (Figure 2-3). NOTE There  may  be  a  protruding  round  head bolt  beneath  the  aft  most  10k  tiedown fitting.    If  so,  remove  and  discard  this bolt. NOTE Ensure  bolts  are  tightened  down  snugly so that washers under bolt heads will not rotate. (5)    Install  eight  10k  fitting  assemblies  (22, Figure 3-2) at the eight locations from which the 10k rings and   screws   were   removed   in   Figure   2-3   and   steps   2- 8b.(2) through 2-8b.(4).  Proceed as shown in Figure 2-4. Install   inboard   special   bolts   (41,   Figure   3-2)   and   flat washers (40) finger tight.  Slide 10k fitting assembly (22) into  position  (under  the  washers  and  bolts)  through  the open  slots  of  the  10k  fitting  assembly.    After  10k  fitting assembly  (22)  is  in  place,  insert  12-point  bolts  (39)  and flat washers (40) and then tighten all four bolts. (6)    Install  outboard  rail/roller  assemblies  (1 through    6)    according    to    the    following    steps.        This procedure is typical for all outboard rail/roller assemblies. NOTE Rings of 10k fitting assemblies (22) must be  laying  flat  for  installation  of  outboard rail/roller assemblies (1 through 6). NOTE Orient all 5k tiedown fitting assembly (21) rings   to   face   inboard   before   installing outboard  rail/roller  assemblies  (1  through 6). (a)    Lift  outboard  rail/roller  assembly  (1  through  6) over 10k fitting assembly (22). (b)  Angle outboard guide rail (47, Figure 3-3; 24 or 42,  Figure  3-4;  or  51,  Figure  3-5)  such  that  bumper  is clear  of  or  just  touching  buffer  board  (Figure  2-5).    The buffer board may be trimmed, as required, for installation clearance. CAUTION At  station  481.780,  self-locking  nut  (46, Figure    3-5)    will    not    allow    excessive movement  fore  and  aft.    This  prevents interference with 10k fitting assembly (22, Figure 3-2). (c)  Rotate outboard guide rail (47, Figure 3-3; 24 or 42,  Figure  3-4;  or  51,  Figure  3-5)  outboard  to  vertical. Some fore and aft movement may be necessary to do this if interference occurs (Figure 2-5). (d)    Attach  both  outboard  rail/roller  assemblies  (1 and    2,    Figure    3-2)    to    the    two    forward    10k    fitting assemblies (22), at station 240.000.  Refer to Figures 2-5 and 2-6. CAUTION Ensure   loading   pole   grounding   cable   is outboard of outboard rail/roller assembly, stations    272.531    to    374.000    (3    or    4, Figure 3-2), at installation. (e)    Attach  outboard  rail/roller  assemblies,  stations 272.531  to  374.000  (3  and  4)  to  10k  fitting  assemblies (22) at station 320.000.  Refer to Figures 2-5 and 2-6. 2-6