The 2nd Edition (1975) of Michael Bowyers' "Fighting Colours" starts Chapter 11 "1943-44: Middle East and Italy" with a paragraph about the Malta Mossies. It explicitly states that the NF II were "in desert camouflage and black undersurfaces".
I have never been able to confirm or deny the veracity of this, can somebody here PLEASE put me out of my misery!

AndyG