Do you think a teensy would fit in there?
I like this setup man. I'm currently in the process of building a similar project with the Raspberry Pi Zero with an original Gameboy case. I am planning on using a teensy in that build instead of using the GPIO for the buttons. You think that board would fit in the case? You have so many similar ideas to the guys doing the "Gameboy Zero" mods, but just enough different to help me learn new things. I may pick this project up next. Can't have too many emulators laying around. 🙂 Good job and keep it up!