Things You'll Need
Instructions
Download the schematics and HEX files for the micro controller from any number of websites offered by electronics hobbyists and gurus like raphnet.net.
Remove the screws from the base of the controller.
Detach the circuit-board inside the controller and turn face it up on your work surface so that the button connectors are visible.
Trace the connection between the input switches and pins of the IC with a circuit tester.
Use your soldering gun to solder connections needed for the controller to the 9-pin male D-sub connector.
Saw off and remove the left over portions of the new circuit board. The majority of the buttons and connectors are no longer needed.
Open your plastic box and place the unit inside. You may either glue it in place or just set it inside. Seal the box with the new adapter inside.