I started this thread instead of replying to the Tee nut thread. It is a bit off topic for making Tee nuts :-)
Bill,
I changed the tumblers on my RV trailer so everything opens with the same key. This place sells keys, replacement locks, and tumblers.
https://www.rvlocksandmore.com/lockskeys/replacement-keys
You may need a special key to change the tumblers. Mine were Global brand. ebay has them. I was not a RV dealer so they would sell me one until I needed to key our construction trailers.
Al

"Crap. You just reminded me again that I need spare keys for the camper shell on my old pickup truck. I have one useable key that I can find, now. I've taken it to a locksmith, and had no luck finding blanks. May have to try replacing the cylinders in the existing locks, IF I can find something that will interchange. Also need to make a new drawer for my tubular SB lathe stand that I got with my 1941 SB Heavy 10L, and find a lock for it. One drawer and lock was missing when I got it. Somewhere in my info stash is a small booklet from the CIA on make keys...  William R. Meyers, MSgt, USAF(Ret.) "