Unfortunately it is not that simple.
The SSL 3.5" disk system uses a SCSI interface with some fairly specific protocols. It converts SCSI to IDE through a Teac FD-1 card.
The drive itself is a rather specific Teac FD-235HF 6700.
Power for the FD-1 is taken from a the modified 3.5 drive, back up the 34way ribbon, IIRC.
I've tried many combinations of emulators on the SCSI and the IDE side of it, even have the developers work along side me.
Still no luck.
The 8" USB emulator, whilst took a bit of time to work out, has been 100% solid for me over the last 5 years.
Anthony.