Mav6 reported making further progress last week by installing main assemblies on the M1400 airship hull.
The M1400 has both internal and external fuel tanks.
The external tanks do increase drag, but the designers want to take advantage of the full lift of the airship to carry as much fuel as possible – for max endurance. There are structural limitations to the amount of fuel that can be carried internally on the power car, hence the need for the external tanks.
Maneuvering valve installation:
Source: The Edgefighter