As it appears to be a standard Mk.II*, I'd go with a khaki green for a Northwest Europe presentation, circa summer 1944. It's a bit lighter than the U.S. olive drab we used in late 1944 - BTW, if there's a data plate on this, what's the mfr date? - and you could camouflage it if they wish.
Check the Softskin and Restoration forums for a great deal of previous dialogue on vehicle colours, including good stuff on the mystical No.2 (Dog Turd) Brown...
