First I put together the Diesel filler: the outside inlet is connected to the tank by a 38 mm (inside) pipe. I replaced the original tank cover with one that had a screw-on connection. On top of that connector I attached a hose connector, and then a 38 mm wide pipe hose could be used to connect the inlet with the tank.
Then I needed to install an air duct, to allow filling of the tank without the air entering the van compartment. The inlet has a connection to ventilate the tank, and that is what I did then connect with a fuel pipe.
Now drilling a hole for the inlet.
Now connecting the fuel hose and the tank ventilation.
