Tim, Good Question!
I sent months researching my 1943 RAF WOT2 Radar Truck, and concencus of opinion was to be the Late 1942 period colours of
Dark Brown and Service Brown, (same as the WOT1 Fire Tender)
I thnk you will find that the picture of the Tilly, is actually a dark print and what looks 'black' is actually Very Dark Brown.
The Jeep question has also interested me, I have a feeling that they would have been all over RAF Service Brown, but again the only colour photo's of RAF Jeeps I have seen are in Desert Sand!
Lets hope someone has the answer.
Jules