As strick as discipline was in the Japanese military back then, I don't believe anyone would be allowed to be that different. Maybe in heavy combat, they could be a little lax on shaves and haircuts. The pictures on Hiroyuki's site he provided does show hairy upper lips were popular.Even in the US military back then, you could never get away with long hair. The favorite saying seemed to be "GET A HAIRCUT!" when I was in.
Uncle Frank
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