greenface6, Welcome to the discussion area!
You really should have started a new thread. This one is huge already and not related to your question.
Your G4 933 MHz QuickSilver is NOT compatible with the
AirPort Extreme card.
Your G4 933 MHz QuickSilver has an internal slot with is ONLY compatible with the original 802.11b
AirPort card. This card is no longer made nor sold by Apple. But you can still find the card for sale on-line at various vendors.
The 802.11b is capable of a maximum data rate of 11 Mbps while the Ethernet port on your G4 is capable of 10/100/1000 Mbps. So the available bandwidth will go down.
I think a better solution is a
compatible PCI wireless card.