Ok - this is what can be found inside the G+ Disk Drives Unit :
This is a view inside :
Notice the 2 extra boards in the box ?
These are what I'd call SCSI <-> Floppy mapping controllers
Look at this a little closer :
On these boards, the SCSI ID is set :
For SCSI ID 1 :
For SCSI ID 2 :
Here is some documentation of this :
http://bitsavers.informatik.uni-stuttgart.de/pdf/teac/FC-1/HW_HS_1100.PDFBtw. - the jumper settings on my drive are the factory preset.
The back says SCSI (sintech - according to your Wiki link SASI is really SCSI-I - didn't know that, thx):
I know these SCSI <-> something controllers when I was playing around with UNIX boxes back in the 90s.
Actually, I still have some for MFM and RLL drives, even for tape drives (don't remember the interface name from memory).
According to all this, I am tempted to think, that a 'standard' floppy could be used instead of the TEAC one (but would have to prove that),
What should be possible is to attach about any kind of SCSI device there when 'just' leaving out the mapping controller