I converted a pole position to a dedicated driving cabinet.
I added two buttons on top the cabinet for ESC and Pause. I added two buttons above the coin door, a player 1 start button and a credit button. I added two buttons to the my control panel, one for a Turbo button and one for Fire. One recommendation is you may want to replace your HI/LO shifter with a 4-way shifter. I replaced mine with a 4-way. You can still use one side of the 4 way to act as a HI/LO shifter. As far as the brake pedal goes, I didn't add one. I can't say that I'd actually use one in a game. If you want to slow down, just let off the gas.
I'm using 3darcade as the frontend, using the steering wheel for scroll through the list and using the gear shift to select the game.