Clockmstr is correct.......
I had an A500 (RocTec) SCSI harddrive unit plugged
on the A1000 bus and it worked fine, even reconized
the 8 megs ram in the harddrive adaptor.
It just sat backwards because the A1000 bus is on the
right side and the A500 bus is on the left side.
To my knowledge the pinouts are the same.