What about the C30-7A, the flat topped C39-8 and camel backed C39-8, the BB40-9W in Brazil, and the never made U18BT?
here is evidence of a U18BT. http://pc.smellycat.com/list/1999-01/msg00081.html
evidence of a BB40-9W. http://www.railpictures.net/viewphoto.php?id=52750