I just had a rootle through my box of drives and found an early Connor, which has two sets of pins.

On some of them, termination is provided on the pins labelled E1 etc., and ID is set at the pins at the end of the drive. See here: http://stason.org/TULARC/pc/hard-drives-hdd/conner/CFA-170S-170MB-3-5-SL-SCSI2-SE.html