I know I've seen a pic somewhere on CG of a 5210something with a small padlock on the latch for its bottom door. In the rare event that I hang up one of my Ltl Acorns without it being in a security case, I'll put it up out of sight/reach and with a cable lock on it, but I'd like to deter someone from opening the door or unlatching the cam from the MM1 module.
A lock with an ⅛" shackle will fit the hole in the latch, but the Master 646 resettable combo locks ("luggage locks") that I have don't work. The inside height of the closed shackle is 11/16", long enough so the lock can be closed (maybe), but then it seems to get jammed up by the law of cosines or sumthin', and can't be rotated so the "legs" of the shackle will hang vertically. When the shackle is inserted in the latch from the from the back, it can't be closed because of the lip around the bottom of the cam.

If inserted from the front, the body of the lock will be extended past the curve of the "backpack."

The little Master brass locks (keyed) that I received with a couple of used Leaf River cams can't be rotated, either, and they can't be closed because the shackles are too short.

Thanks in advance for any recommendations.