Now im no expert with this stuff so if im wrong step in fellas but its working in firepower.    

Before installing your super cap turn the game on without batteries and with a multi meter measure the voltage between the + and - battery terminals.   If you have 5v then you can leave the board as it is if you are getting no voltage then you will need to run a jumper across where the diode is to allow the voltage back to charge the capacitor as these board use standard non rechargable batteries so the diode stops the 5v trying to charge them when the game is on

The diode can be removed if you felt the need.

Red line is the Jumper and the cross is the diode to remove