For the diesel you need a supply and return line as well as a vent for the tank. Some of the diesels have a sediment filter as well as a fuel filter. The fuel filter is in the engine bay close to the injection pump. The sediment filter is on the RR frame in front of the rear wheel. (not all applications had this). The Td5 tank had the fuel line coming out of the top. It has a hard line that goes down into the swirl pot and a rubber line connecting the outflow to the hard line on the frame crossmember.