Chris's research and thread describe the changes made to the Little Ten Hundreds. http://www.frisco.org/vb/showthread.php?t=2014 In this undated image, 1013 pauses at Clinton with number 20. Many of the changes made to the spindly Pacifics by the West Shops are apparent, i.e., Walschaert valve gear, twin NY number 2 air pumps, front-end throttle, piston valves, and the 50" diameter, man-hole cover trailer wheels.
