Apple PC Serial and Parallel Card - Manual (Page 59)

Preparing the slots
8 Unscrew and remove the metal port access covers for the slots you need.
If you are installing the PC Serial and Parallel Card at the same time you are
installing a PC Compatibility Card, unscrew and remove the port access
covers to the first two PCI expansion slots.
If you already have a PC Compatibility Card installed in your computer, leave
it in place. Unscrew and remove the port access cover to the second PCI
expansion slot.
Keep the screws; you will reinsert them later.
9 If you have a card in the third PCI expansion slot, remove it.
You will have more room to install your PC Serial and Parallel Card if the
third slot is empty. See the user’s manual that came with the card for
instructions on how to remove it.
Port access cover
Remove the screw that holds the port access cover in place.
PC Compatibility Card
Second PCI slot
(Front of computer)
59 Installing the Card in a Power Macintosh 8600 or 9600