You need to fill some requirements before put an HD inside your A600:
- What version is the kickstart? If under 37300, none HD will work.
- Whit version 37300, up to 40Mb work (don't count on it, I use that version with a 2Gb hd, no flaws).
- Whit version 37350, up to 2Gb.
Notice you can buy a newer ROM revision (3.1, aka 40.063) for your A600, habilitating it use up to 4Gb withuot any software hack/patch.
BTW: you can't use SFS instead FFS because the processor is a humble 68000.
So the only route is patching the SCSI.device with IDEfix97/99 and applying NSD or TD64 patches after that.