I was unable to find a full size good working 5.25" drive to add as the second drive; the pin-out of the old SA400 is partially different from that of more modern drives. Finally I found a narrow 360 KB Matsushita drive which, when configured as drive A:, gave a good working ensemble. The internal connecting cable is the usual 34 pin flat cable with two card-edge sockets, but not the later introduced "IBM twist".
