I meant maybe it would be the easiest solution if you're gonna remove the possibilities of changing those (american soldiers and officers) clothes...in order to avoiding unneeded graphical bugs...
about americans in Bletchley Park: I was wrong...I think they are not really soldiers, the OSS was not a military organisation:
http://magyaritasok.hu/gallery/hu/de...5-17-06-68.jpg
(- Hello! I'm James Bowman from the OSS! We've came for some ducuments! Have you been informed about it?)