AnimeOTK - Spanker for M/f scenario

The basic concept is that a young girl, mid to late teens depending on what era this is set in, somehow manages to con her way into the military in the guise of a boy. Don't read too much into it as the major plot hole would be that a physical examination, which are pretty standard practice, would naturally ruin this guise. I thought of that and I still think that this plot could be potentially amusing so overlooking the obvious plot hole I would still like to attempt this if anyone's interested. Preferably it would be a historical setting but that said if someone absolutely wanted to do a fantasy/sci-fi futuristic setting I could possibly be interested in that as well.

If anyone's interested in this scenario feel free to respond to this or send a PM and we can discuss plot and specifics.