Apple Macintosh 6500 - Manual (Page 204)

4 Remove the PCI card from its static-proof bag.
Hold the card by its upper edges to avoid touching any connectors.
5 Supporting the adapter fence with one hand, insert the card into the PCI slot so that the
card fence matches up with the opening where the port cover was and slides through the
slot in the adapter fence.
Card fence Slot in adapter fence PCI slot
Adapter fence
Connectors
204 Appendix B