Update, got mad at keys, I had 6 different keys for 6 locks around the old 78.
Started ripping them apart to rekey them to one key. I should have taken pictures but I forgot.
I had one lock that did not work, although I had the key it would not turn. Lucky for me it was an unlocked one. It started the whole process. Found a few national locks (cabinet ones) that had interchangeable tumbler pins with the Hudson locks on my 78.
After stripping all the pins out and sorting them by the sizes (its easier than it sounds), I picked the one key that I could use all the pins to make all the compartment locks work from the one key.
Here is an example of a fit and not fit key.
So the one on the right does not fit the one on the left is smooth. Those aren't my rv locks but they work for an example.
WARNING! Don't loose the springs, replacements will be hard to get.
Once stripped you can put the key in the lock. taking a tumbler in the lock upside down, and using the lock cylinder as a guide for what will fit. the break (or hole in this case) should line up the outside of the cylinder see picture, it should sit a slight bit above due to reversing the contour.
After you figure out the position of the tumblers, reassemble the lock cylinder (don't forget the springs you were careful not to loose.)
Your result will look like the other one in the first picture, all the tumblers line up flush and will function with the key.
I was lucky that most of my locks were able to change over to one key by moving the tumblers around to match one key. I did have to switch one whole lock assembly for another one that I keyed in the same way to make it also the same.
Result is I now have one key for all compartments, one RV door key and one chassis key.
Now with only 3 keys, less bulk and weight in the pocket = More happiness.