I have two hard drives on my primary ide channel. During rh 7.3 setup I told it to install the boot loader on the second hard drive. When I tell my bios to boot from the second hard drive it hangs ...
If the BIOS can't see it, then no bootloader in the world will be able to boot off it, that I'm aware of. You could certainly write one, but it would require including enough PCI and firewire support ...