Hi Fabrizio:
OK, more exercise for the tired old brain.
For some reason, the word "filo" found on some of my photos did not register correctly with me and I assumed it meant "File #1/2 etc.". I found what the word really meant in Italian and once again hit the Google trail.
So, what we have is, I believe, several three axle trucks based on the Fiat 672F bus chassis and one two axle truck based on the Fiat 666 truck chassis. The other "name" for these vehicles is Filocarri or even Filocamion.
I hope that is what you are looking for.
Bill