take the stall near the wall.
besides, who gives a s**t (serious pun intended) if the dude in the next crapper sees you're armed? Taking the gun out of the holster and placing it somewhere or holding it... comon, your holster will still be attached to your belt and now they will see a GUN holster with no GUN in it. Try this, don't let your pants drop all the way to the floor, lower them to mid thigh, then close your belt on your thighs while you're sitting there. I mean really... I can't believe I've read this far or typing this much, but are we really discussing how to maintain concealment while taking a dump???
PPQ M2, G-19, PT-140 Pro, PT-111 Pro, Core-15