Hi - I'm really interested to see this layout!
My main passion is WDLR equipment & rolling stock - based at the Moseley Railway Trust, we've now restored WW1 20 & 40hp Simplex locos, a Class H watertank & 2 Class D (currently finishing them). There are more vehicles to come. It may be of interest, that contrary to popular belief, during the restorations we have determined that the Class D - H stock (& probably others) were originally built/finished in "Battleship" grey - there was also anecdotal evidence of this in notes written at the time. More recently I have found that the lettering on the vehicles should be a yellow & not white (I'll have to re-do this on our Water Tank - as we initially gave it white lettering). The grey we have used on our wagons was matched from original surviving paintwork.
The Watertanks were the only vehicles I know of, to have received some form of camouflage - this was applied in the battlefield. Presumably the galvanised finish of the tanks when supplied made too much of a target for enemy snipers/field guns!
The Petrol tractors were all variants of "Olive Drab" - our 40hp Protected was matched to original paint found during the restoration.
You can see more of our work at www.mrt.org.uk or via my own WW1 website - www.wdlr.org.uk
We are planning a large WW1 themed event in September 2014 - I would be very interested to invite this layout to attend please!
Keep up the good work!
Cheers,
Gareth