WC 1231 and 1236 wait for their next heavy switching assignment near the yard office at Shops Yard, North Fond du Lac, WI. The Wisconsin Central was a rolling museum for older EMD power. SW9 1231 came from the Houston Belt, HBT 31, built Aug. 1951. Compare it to no. 1236, former SP SW1200 no. 2287/1622, built Nov. 1965, just before the introduction of the SW1000/1500 series.
