I think you should pretend you are adding 30GB drive as slave (see FAQ). When done, drop to shell and copy everything from /drive0 to /drive1 (cpio is the command I would use; ordinary cp will do, too), but delete files describing database (IIRC, database, playlists and fids in /drive0/vars). Copy whatever else is of interest (custom SW, config.ini, whatever). Finally, install the new disk as the only one and perform a sync or two to rebuild database.

Good luck!