I tried...
Broken Grub menu: boot to the menu, drop to a console and boot openSUSE direct
...and it seemed like it booted, but it didn't go to the GUI. It ended up asking me for linux login. I tried typing but couldn't. As a note, I have to add noacpi acpi=off to my boot menu to make the mouse and keyboard work.
I tried...
Reinstall Grub in the Master Boot Record and link it to the existing Grub menu in openSUSE
... and it caused the same error as the first time. Error 18: file not found. BIOS doesn't support booting from above such and such cylinder.
I tried...
Boot from the SuperGrub Disk: see
Super Grub Disk Homepage
... and again got the same error as originally
I couldn't try the last option in your link because I could never boot into SUSE without that second hard drive connected. I assume if I choose MBR in YaST in my current configuration (with the sdb still attached) it will just put it in the MBR of sdb, which wouldn't get me anywhere.
I feel like I need to get GRUB installed at the beginning of my hard drive. Is there any way I can move that EISA partition at the beginning of the hard drive to that secondary hard drive in SUSE?