Apple PC Compatibility Card 12-inch card - Manual (Page 37)

Closing the computer’s chassis
22 Close the chassis.
Make sure that the support arm is disengaged. Make sure the cables you
connected are away from the heat sink and center support post.
Support arm
1 Disengage the support arm from the hole on the floor
of the bottom chassis by lifting up on the support arm.
2 Gently swing the top part of the chassis down until it rests securely on the bottom chassis.
Be sure that you don’t pinch any of the cables between the top and bottom parts of the chassis.
23 Installing the Card in a Power Macintosh 7200, 7500, or 7600