you are on the right way to do that as all of your thoughts are fine. you just need to buy the hard disk. avoid to use more than 1gb for boot partition, you will never need even this space for workbench. think about use the sfs on the new disk and not ffs. it's faster and most safe and working better with large partitions.
sfs use the os3x 1.254 version.
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before you remove the cdrom, remove the cd driver from devs:dosdrivers. you will put it back again when reconnect the cdrom.
