Milwaukee Road EMD SDL39 581 and Alco RSC2 577 rest at Viroqua, Wisconsin in August 1974, having completed their leisurely trek over a grass-grown branch line. All examples of the SDL39, with its short 55-foot frame, were built in 1969-1972 for the Milwaukee Road which needed a lightweight road switcher for branch line service to replace the aging RSC2. No. 581 was wrecked and scrapped in 1983. As for the RSC2, Alco had constructed the Milwaukee's version of this six-axle road switcher in 1947. It is of note that the Alco unit was originally numbered 977, then bore the number 581 (the same as the SDL39 shown here) before being renumbered to 577. I happened to come upon this branch line freight during the transition period when both models were in use. The Milwaukee Road abandoned the Viroqua branch in 1980, but it was operated until 1981 by the Chicago, Madison & Northern Railway.