Thanks for the awesome tutorial, it answered a lot of questions I had.
I just tried running through it several times with the linux iso from xboxhdm (pausing before HD detection and swapping drives using primary master slot [I disconnected my main drive and set the bios to boot off cd]). On the xbox I'm trying to reapir, the M$ logo does not come up, so I waited until the hard drive stopped clicking, right before the error comes up (error 16) and plugged it into my PC cable. After hitting the spacebar, my pc almost immediately recognized my xbox drive (showed the model number on the bios screen) and booted up to the cd, once I got to the screen where you type xboxhdm, the program booted and told me there either wasn't a drive installed on the primary master (it recognized it on the bootup as the primary master) or the drive wasn't unlocked.
My question is, how come my pc recognized my xbox hd at the bootup screen but not from the program? I followed the tutorial to a T, and even tried adding the drive through Windows XP, when I tried to scan for hardware changes, it didn't do anything at all. Am I missing something, or is it possible that their is a corrupt file on my HD that's preventing my xbox HD from unlocking at startup? Thanks for any insight anyone can give.