MILITARIA! ~ a WWII collector's dream! 1940's "Allied Personnel Only" porcelain sign!

I recently acquired this large (30X17 inches) sign from an elderly man who told me that his uncle brought it home from "a remote base in the Philippines" at the end of WW2. It has enamel on both sides - black on the back, white with black lettering on the front side. It is fairly heavy and appears to be made from a sheet of approximately 20 gauge steel stock. The darker areas on the back (reverse) side are in shade. It's all the same color.