Schnapps: Traditional Guatemalan men's clothing consists of a pair of short trousers, or breeches, worn over longer pants that show through beneath them. There is a similar Mexican style in which the outer trousers are unbuttoned below the knee, showing the legs of the drawers. You can see this in any number of James Walker's Mexico and California paintings. But these are both Spanish colonial styles which have next to nothing to do with the largely Anglo manpower force that fought the Civil War.
When I started reenacting, my Rev War unit used the axiom that it's better to do without than to use the wrong one. I carried this into Civil War. I didn't have civil war drawers; they were exotic and elusive. So, se rule #1 above. There I was at 125th Gettysburg. 4 days in the dust, heat and wool with nothing between me and my kerseys. By Pickett's Charge I walked like an old dragoon. After day 2, those trousers might as well been sandpaper. All I'm sayin' is that sometimes the axiom stated above needs to be mitigated with a little good common sense.
Pine River Boys, Co I, 7th Wisconsin
"We're... Christians, what read the Bible and foller what it says about lovin' your enemies and carin' for them what despitefully use you -- that is, after you've downed 'em good and hard."
-Si Klegg and His Pard Shorty