This may be what you are talking about. I have a STacy 2. I believe it is an early one as it has been upgraded to 4m by populating the internal slots. No upgrade was added. The interesting thing is the "port" is not added but just showing the trace on the M/B. I wonder what kind of connector was used and if it could be made active?
It is next to the DMA port so perhaps it was meant to be used in a future version?!?!?
I am curious because I am thinking to remove the internal SCSI drive and add in a SD card. If the internal hard disk controller is not needed, I can remove that and get more space inside for further mods...
I will post a picture in a day or so...