The Gentoo live-cd shows my drives as "hda", so I followed the Gentoo handbook and configured my partitions as "hda". However, the boot failed because, when booting into my kernel, it wanted to refer to the partitions as "sda".
So, I edited my fstab and grub's menu config file to refer to partitions as sda, and everything booted successfully.
Was this the right thing to do? Any other steps you would recommend regarding this? Is it surprising to you that a new minimal Gentoo livecd would refer to things as "hda" in the first place? And if so, do you suspect there may be some issues I need to resolve?