I installed the former Wavelan Silver PC Card guts in my friend’s mom’s iMac G3 last Thursday evening. The card isn’t fully seated, but it appears to be functioning correctly! For people concerned about getting the card fully seated, it would be best to clip off one of the plastic AirPort card holder’s that is attached to the board (its whitish-transparent plastic that is only useful if you want to give the true AirPort card more support). Still, without clipping this plastic support, the card seats 90% of the way.
AirPort Card for $30. Done.
If I ever stop back over there, I’ll snap some pictures and post back.