Abstract: A cartridge rear closure system for a delivery van allows ready exchange of rear door(s). The system includes a frame for a rear door structure, either fitting around a rear end opening of the delivery van cargo storage enclosure, above a rear bumper for the delivery van. The frame either includes or receives door(s) or a door insert of a first type, and either the frame or the door insert is interchangeable with another frame or door insert for another rear door structure including door(s) of a second type. The types of door(s) may include barn doors, a tambour (roller) door, and a split tailgate/liftgate. Latches securing the frame or door insert preferably include a quick-release mechanism. The roller door slides within roller rails and, when raised, either onto roller rail extensions or into a roller door casing.