Great Northern's 36-unit GP20 fleet consisted of two specific orders. The first group, 2000-2017, differed only slightly from the second order. The original units, such as 2006 and 2000 above at Minneapolis on June 20, 1965, illustrate the only visual difference, with their bell mounted on the front of the long hood above the walkway. The second order, 2018-2035 the bell location was on the long hood just ahead the cab behind one of the 48-inch fans to help keep them from freezing during the winter months. Photo by R.R. Wallin, from my collection
