OK, just finally finished the G3 off.
I've put in an OCZ 90GB Agility SSD drive for the OS, a 1TB Samsung for general storage and a 500GB Western Digital drive as I am dual booting Lion and Snow Leopard (Snow Leopard because I need it for the Canon scanner that I have as there is no Lion driver for it)
I also replaced the temporary Intel cooler with a Scythe Kozuti low profile cooler.
The Kozuti is only 40mm tall so there are no clearance problems in a G3/G4 case
I also made myself an Airport card from an Apple PCI-e wifi card and a mini PCI-e adapter bought from Ebay, seen here next to the graphics card.
Due to the position of the PCI-e slot on the mobo I had to separate the backplate and make a small bracket to support the card.
Recognised OOB in OSX
The backing plate is mounted in a lower PCI slot.
Getting good wireless speeds from it too
Forgotten I had this keyboard and graphics tablet but they match the G3 perfectly
Am pleased with how it turned out and it should last a year or two as a backup machine and to run the scanner from.