TM 10-3930-669-20 7-15.  MAIN POWER SWITCH REPLACEMENT (CONT). (4) Remove screw (10), lock washer (11), and knob  (12)  from  switch  (13).    Discard  lock washer. (5) Remove nut (14) and switch (13) from cab wall (15). b.  Installation. (1) Install switch (13) on cab wall (15) with nut (14). (2) Install  knob  (12)  on  switch  (13)  with  lock washer (11) and screw (10). (3) Install  wire  (9)  on  terminal  (3)  with  lock washer (8) and nut (7). (4) Install  four  wires  (6)  on  terminal  (2)  with lock washer (5) and nut (4). (5) Lift    two    terminal    covers    (1)    on    two terminals (2 and 3). NOTE Follow-on Maintenance: • Close engine access panel (TM 10-3930-669-10). • Connect batteries (Para 7-48). • Remove wheel chocks (TM 10-3930-669-10). END OF TASK 7-34