It depends on what version of AmigaOS you are running. AmigaOS 3.5 or newer supports 64-bit addressing once setpatch is loaded from the boot partition. There is also a patch for AmigaOS 3.1 that can be downloaded separately. This will allow full-capacity drives to be used with those systems as long as the boot partition is 2 gigs or less.
Also, you might consider SmartFilesystem rather than FFS for the larger drives and partitions since an invalidated allocation bitmap can take a long time for the disk-validator to run.
