Lift the Cub's hood cover up and use a wrench to remove the negative battery cable.
Lower the mower's cutting deck to the lowest setting by moving the deck control lever. Also make sure the brake is engaged.
Locate the reverse PTO safety switch under the right side shifter. The switch can be accessed by removing a small piece of trim with a screwdriver. Disconnect the switch by grasping it and unplugging it from its socket.
Make the repairs you need to make with the reverse PTO switch disconnected and then reconnect the switch. Replace the piece of trim along with the retaining screw.
Replace the negative battery cable with the wrench and close the engine compartment lid.