Dell PowerEdge C6145 - Manual (Page 179)

Installing System Components | 179
6 Remove the screws that secure the upper middle plane to the middle
plane holder. See Figure 3-38.
7 Disconnect all the cables from the upper middle plane.
Note the routing of the cable underneath the tabs on the chassis as you
remove them from the system. You must route these cables properly
when you replace them to prevent the cables from being pinched or
crimped.
8 Lift the upper middle plane out. See Figure 3-38.
Figure 3-38. Removing and Installing the Upper Middle Plane
1 upper middle plane 2 screw (6)
3 stand-off on middle plane holder (2)