At the multi-purpose/box-type delivery van, attachment and base group form a self-supporting unit. Supporting parts of this self-supporting unit must not be removed without being replaced by another component. Baffles have no supporting function. Modifications, even the complete removal, are permitted. If car-body parts are to be modified or to be installed, it is only permitted to weld if bonding is not possible.

• Cut-outs in the side wall
  If profiles are cut in order to install cut-outs (windows, doors, bonnets, ventilation, air exhaust, etc.), the cut-outs must be reinforced by an enclosing frame and must be welded to the cut profiles.
• Roof heightening (plastic roof)
  refer to item 3.6, Roof design

At closed bodies with partition walls ventilation slots are located in the partition wall and the D-pillars. At car modifications it is only allowed to cover these ventilation slots, if new slots are produced in the cab instead. For example in the cab doors.