I've thought about doing exactly this to a Unicomp Ultra Classic. The problem is the utility of the result. To be a useful "Buckling Poker", it needs Fn layering. This could be done with a Teensy or something, but it would be a fair amount of work. The Ultra Classic is 104, so you have the extra keys you need for Fn. Another idea is to start with a Model F XT, which needs a Teensy anyway.