Still not working. I keep getting errors when I run grub-install:
grub-install /dev/hdb
/dev/hdb1 does not have any corresponding BIOS drive

Not good. Then I used the other name for the drive, hd1, and got the following messages:

grub-install '(hd1)'
sed: -e expression #1, char 12: Invalid reference \1 on 's' command's RHS
sed: -e expression #1, char 12: Invalid reference \1 on 's' command's RHS
Unrecognized ls output: Not found or not a block device.

After a bit of googling, I came up with this link:
grub-install bug
Which has a patch by the author of grub himself. This is over a year old, and the new gentoo installation of grub does not include it yet? Oh well. I manually changed the grub-install script and ran it again, and it ran without the error!

Fixed, right? Not quite. I still can't get into the grub menu when I reboot.

GRUB Loading stage 1.5.
GRUB loading, please wait...
Error 15

*sigh*