I tried to install FC6 on my Digital Audio G4/466 desktop, and got all the way through with out any troubles only to find that my system wouldn't boot. After Googling around, I decided to use my wife's OS X install CD to "initialize" the HD and copy the OS9 drivers onto it. I added one hfs+ partition (20 GB), then left the rest as free. During the install, I chose to install on the free partition only, which finally gave me a bootable system.
Is there anyway to do this *without* any Apple Software?