HP 98568A Installation Instruction page 108

HP 98546A Display Compatibility Interface
Figure 5-5.
Installing the interface
e. Using your thumbs, press the graphics (top) card into its slot first. When
it is securely seated in its slot, its extractor levers will be even with the
back of the computer frame.
f. Place the ribbon cable between the two cards, then tighten the thumb
screws on the metal end plate until the end plate is flush with the back of
the computer.
5-12 Adding Interface Cards