The guide worked great for me on a similar system. There's a few notes I can add.
After initially installing Snow Leopard, I had to switch discs back to iBoot to get into the OS. After the first time, I didn't need the disc in the drive to boot.
I had to fiddle with the sound to get it to work. I ended up downloading VoodooHDA from their site but still didn't get it working. The trick (which was in your guide) was unplugging the power from the computer and holding the power button, then restarting the system.
I've had 2 kernel panics and 2 complete freezes in a few hours of running the machine. It seems to be more stable now but is there anything I can tweak to get more stability?
This probably isn't the right place to ask but does anybody know of a kext for a Gigabyte GN-WP01GS PCI wireless network card? I think it uses the RT61 chipset. Right now I'm running a really crappy belkin usb wireless adaptor but it doesn't get great signal.
Thanks for the guide dotmerix. I didn't make it very far on my own.