Thank you silverkid! I didn't realize that the problem was the kernel. I have successfully installed OS X 10.6 using chocolate_kernel. Sound and LAN are working, and all of my SATA and IDE drives are recognized! I have a few problems now that I'm trying to get sorted out: One is that USB flash drives are not recognized when I plug them in and my USB mouse and keyboard only work most of the time. However, I'm sure I can find a kext to get USB working. My plan is to then upgrade to Lion using UniBeast and the Lion installation app. Since Lion has native support for my graphics card, the Nvidia GTX 460 (GF104), I'm not going to try to install graphics drivers in Snow Leopard - it boots fine with GraphicsEnabler=No.

Once I get Lion installed, I should be good! However, I'm being optimistic. If I encounter any more problems, I'll post them here. I'm documenting what I do as I do it, so if I get this working, I'll be able to start helping others with similar hardware.