The project is pretty forward. The "RUN" buttons are wired to pins 3 (LEFT) and 4 (RIGHT) of the controller port and the "JUMP/THROW" button is wired to pin 6 (FIRE). All buttons return to pin 8 (GROUND).
Few components are required: Three buttons, one cable and one box.
The buttons used on this project have low profile
The low profile buttons allowed to use a low profile box.
The buttons were disposed like the original track and field controller
And here's the finished controller.
Do you by any chance have the Link/files for the Plastic case/box?
Also how are you finding those buttons? If they are great, can you please share their part number as well so I can get something which you have tested.