Brake Switch Wiring

[rrenner]

I'm using a speedway 20 circuit wiring harness and am up to wiring the brake switch, instructions say orange #40b to imput side of switch and white #17a to output side of switch. I am using the stock lever arm switch activated off the pedel arm. My questions are, which contact on the switch is which, or does it matter? The harness does not supply a wire to run to the back, I assume one runs from the switch to the brake lights, from the output side? Any help will be apprecaited. Rob.