I finally got around to working up a redundant locking system for the camper. The tail gate is up as far as it will go, to an angle about 30 degrees short of vertical where it makes opening the door impossible. It secured there with a chain and padlock contraption.
(Those of you with RV experience know that their factory locks can be defeated with a powerful wish.)
It won't even slow down a pro, but it should discourage your casual miscreant looking for easy wherewithal to acquire pharmaceuticals.
As a bonus, the license plate is visible, robbing Officer Friendly of a reason to stop me because he's bored and wants to practice his consent-search spiel.
"Why, yes, officer, I do mind you just looking through my vehicle ."
This would have gone much easier if the camper were on inch shorter or the bed one inch longer.