I successfully did it with some 308 win brass, just for kicks. It took a lot of work, and I do not feel that the time invested was worth the results. That is, unless thats all that you have to shoot. Like you, I just wanted to try it. Personally, I would convert them into beer money, via the scrap yard.
I used an end mill to remove the anvil and a small drill bit to drill the flash hole. I don't remember if I had to deal with a different diameter or not, this was a long time ago. Good Luck with your idea, Lightman
Edit to add, they make a tool to deprime them with that does work kinda like a can opener. You can also use a hydraulic method, but thats kind of messy. I would be worried about a shotshell primer being able to handle the pressure. Lightman