Remove all of the screws holding the two halves of the motor housing together. Now split the motor halves apart. The wires are likely soldered to the switch. Snip the wires off of the switch as close to the switch as possible. Strip 1/4" of the insulation off of the wires and re-solder the wires to the new switch using solder and flux. Now reassemble the motor housings in the opposite way of disassembly.
