Common Manual: Parking Brake
This pages provides installation instructions for the option parking brake for the SL-C and GT-R. Not all cars will have a parking brake since it is usually not needed for track cars, and is not required for road use in some jurisdictions.
The brake lever can be mounted on the center spine as is shown here, or beside the driver’s seat between the seat and the outside edge of the chassis.
Mounting the brake lever as shown allow the cable to pass through to the rear through the fuel tank opening that is also used to pass the shifter cables. The picture shows builder-created brackets that mount the brake lever.
Instructions from the manufacturer can be found here.