Here's how it goes. Get a hold of the master password from TEAMASSEMBLY and use ConfigMagic to unlock the drive. How? Turn on your xbox with a bootable drive, and run configmagic. Once you're in there, pop the IDE cable out of the HD. Power on your PC with the locked drive hooked up (NO IDE HOOKED INTO IT, though, just to give it power) and plug the xbox's IDE into this drive.
Use the master password then to unlock it.
If you need to run it in a non-modchipped box...
Relock it with a generated key from liveinfo... to do that, pop the now-unlocked drive into your computer, and load liveinfo. Select the eeprom.bin from your xbox's 'C:/backup' folder (to create one, run evolution-x and hit 'backup'). This will give you a 'unique HDD key' which will generate the correct password for your WD drive. Use either hdlock.exe or ConfigMagic to lock it with that key.
Hope it works!
Don't ask how to get the master password (honestly, I don't know) but I know it's floating around here somewhere. Maybe someone on the board knows it. If you do find it, PM it to me. I'd be interested in having it..