Thanks for the heads up... Even though my ASUS drive had an 'a' in the model number on the drive (DRW-24B1ST a/BLK/B/AS) the drive had FW 1.04 and looked exactly like an iHAS 324B I'd purchased at the same time. Also once flashed and converted (following XeoNoX's directions) the ASUS seems to function properly as a 524B AL2A drive.
THANK YOU! Your instructions were exactly what I needed. The only thing I'd add is to be a bit more specific about what FW .exe to use to flash the drives initially. For the ASUS I needed to use the Flash utility to flash an unlocked stock iHAS 524B .exe from C0deKing's site. For the 324B I was simply able to use the .exe from the unlocked stock iHAS 524B on C0deKing's site and not go through the Flash Utility.
Also, once the drive was converted over, I updated them to the newest iHAS 524 FW (AL2A), restarted and enabled all the options with the settings utility as well as changing bitsetting and region codes. Finally I tested each drive with a few burned discs to make sure they did indeed function properly.
Thanks again for all the help!