Announced in early 1990 to go with the Waaargh! the Orks book, but not released until Orktober. The parts are shown in the 1991 catalogue here.
RTB14 Space Ork Battlewagon - Box Back Enlarged
RTB14 Space Ork Battlewagon - WD129 (Sep 90)
RTB14 Space Ork Battlewagon - Box Art
RTB14 Space Ork Battlewagon - Box Back
RTB14 Space Ork Battlewagon - Instructions