Looking for a way to force playing Super Mario Bros. two player? Well look no further. Thisissafety over at instructables has made some instructions on how to make a Giant NES Controller for you and your friends.
I also made up some blueprints for myself to follow. I photocopied my controller and placed a sheet of tracing paper on top of the regular paper that the controller was copied on to. the reason i did this was so i could write and erase measurements and whatnot. I then took calipers and measured the actual controller in millimeters and just transfered that to centimeters. These measurements are more of a guide line than anything.