The model has now had the camo painting started and instead of spraying I opted in the end for brush painting. It saves hours of tedious masking and even though a couple of coats are needed for the colour intensity it's far easier on my sanity. Also as it's a hard edged pattern I can't see the need to mask when a brush will do just as well.
I used vallejo black grey with a drop or two of flat black and panzer aces Italian tank crew. Both are slightly lighter in colour but as ever they will darken with weathering later.