1989 GMC Truck Box for sale. The box measures 6 feet and 6 inches (short box). There are some minor scratches in the paint and some damage to the chrome however the truck box is rust-free and suitable for a swap onto your truck. The canopy on the box is damaged and could be removed, included, or sold separately for $40, your preference. Other rust-free body parts available as well; doors, hood, and front fenders.