We have seen the NES inside a NES controller and here is another mod, which put the NES and NES controller in a light gun. Seems this light gun NES is just for fun as it looks less comfortable to control.
The problem? This just looks so uncomfortable to use. I’m all for creative mods, and I salute the person who took the time to do this, but beyond proving that it’s possible to cram a NES into a light gun, I’m not sure what the benefit is.