This is the trayback kit, I liked it as it would give you a super nice cab and allow you to make the rear end anything you want, I saw one that was ready for paint in a weekend from being driven in as a running but rotten 5 door to truck cab, I always liked the idea of Land Rover using the Discovery platform as a truck cab that could offer flat bed, drop side, tipper bodies, this means you could build the rear end up as you want, perhaps even kitting it out as an onsite mobile welding rig with diesel welder/generator, oxy acetylene bottles, compressor and lock up for your tools.
Discovery Series 1 Tray Back - Long Ranger 4x4