GP7 610 and Caboose 1704 by Frisco.org Posted on October 2, 2018 GP7 610 and Caboose 1704 GP7 610 and Caboose 1704 (location unknown) in July 1973. This entry was posted in Slides and tagged 1704, 610, Caboose, Electro-Motive Division, GP7. Bookmark the permalink.