The only honest answer I can give is 'don't know'; however -
During the early part of WW2, my mother's father was a mechanic working near Liverpool. A passing Luftwaffe plane ditched it's bomb load one night, which by chance wiped out his workplace and most of his tools with it. He subsequently found work with a firm in Southport who had the task of receiving military road vehicles coming over from the US into Liverpool docks as deck cargo, and making them service ready. Apparently (!) all sorts of tools fell out of various nooks and crannies of these vehicles, some of them dropping into the tool boxes of various mechanics (strange how that happens, isn't it?).
I still have some of his tools, including a number of clearly American manufacture. Apart from the maker's marks, they have no applied markings at all - certainly no US government or army identifications. I don't that can be taken as proof of anything, though - except that on occasion the Good Lord has strange ways of providing what's needed!
