I think you need the tool that punches them with the codes Steve. No expert on them though. Wayne I know from Carlisle, man he was schooling me on key differences tons to know about them actually.
I own several curtis and ilco key guns as well as code books. I also have grinders and punches and cylinder pin kits as well.
You're right, there is a ton to know about them. It isn't one size fits all, but I've making same key kits a have a lot of luck with them.