Mazda RX-8 Workshop Manual page 2329

18. Press the interlock cable lock piece in until it is locked.
CAUTION:
Applying a load to the interlock cable while pressing the lock piece in can affect
the lock unit operation.
19. Remove a 1.5 mm {0.06 in} round bar or similar from the lock unit hole A, B and C.
20. Connect the brake switch connector with the brake pedal released.
CAUTION:
The clearance between the brake switch and the brake pedal is automatically
adjusted to the correct amount when the brake switch connector is connected