IBM 9080-M9S Manual page 495

Figure 426. Replacing the top cover on the PCIe adapter cassette for the 9080-M9S system
8. Replace the side cover on the cassette.
a) Place the side cover on the side of the cassette.
b) Slide the side cover in the direction that is shown in the following figure until it latches securely.
PCIe adapters 489