Apple Power Macintosh 5400 series - Manual (Page 152)

7 Connect the PCI card and the PCI card adapter.
Place the adapter on a firm surface, then press the card firmly into the
adapter. You may find it helpful to place the card and adapter near the edge of
a table with the metal edge of the card hanging over the end of the table so it
doesn’t block the card from being inserted completely into the adapter.
8 Align the PCI card and adapter over the PCI slot.
PCI slot
PCI access port
Vertical plate
PCI card
PCI card adapter
140 Appendix B