This is a late version of the General Electric EF4 "Little Joe" purchased by the Milwaukee Road. Originally these units were delivered with fully functional cabs on both ends of the locomotive however the "B" cabs were later used to house and cool electronic equipment, rather than serve as a second control cab. Consequently the windows were blanked out and ventilation ports were installed. This particular model features typical details found on these units as they existed in the later years of their service. The pantograph mounts are spaced to fit Kato GG1 pantographs as drop ins. There is no direct fit mechanism for this model so you'll have to be creative although the axle spacing will match most 6 axle EMD models. Shapeways modeller
SteamMonster was generous to provide a meticulous step-by-step pictoral guide to his Kato GG1 chassis conversion. Take a look
here! (
http://s7.photobucket.com/user/63Hofnerbassman/library/Shapeways%20Little%20Joe%20build?sort=2&page=1)