Thanks all for the additional information. Circling at 1,000 ft AGL (1600 MSL) probably would have been the better choice given the flow of traffic that day.
13C had a PAPI. I did not wish to have my F/O head's-down tuning LOC and setting HSI's during the circle. Rather, I used the capablites of my FMS. I used the FIX page to set a fix on RW13C and extend a radial out on 316', the runway centerline. I can do this in the Collins 6100 series FMS. I understand that this is not possible in the Simth's or Honeywell FMS's the airliners use. I then used the track bug to be certain that I was parralleling the outbound downwind leg and the base leg.
The actual circle worked out well. It was just uncorfortable seeing all the people on the ground waving (pointing?) at me!
Thanks again. I'll keep the suggestions on begining the circle at ERMIN in mind for the next go-around into MDW!
Rich