IBM 9080-M9S Manual page 588

Figure 506. Connecting the front power cords
4. Position the cover (A) on the front of the system unit as shown in the following figure, so that the four
pins (B) on the system match the four holes at the rear of the cover.
Press the front cover into position.
582 Power Systems: Removing and replacing parts in the 9080-M9S system