Nice Pictures Owen.
The RAF blue Norton is a bit of a contradiction as RAF vehicles mostly weren't blue during the war years and this one has a wartime WD (Not RAF) census number. If the number C4389970 is correct for the frame number, it was indeed part of an Army contract.
Photo No. 15 by the way is actually a Fordson (a WOT6, I think) Probably quite a reliable 3-tonner. I've not heard of any particular problems anyway