Wash the underside of the Craftsman mower and the top of the mower deck before beginning installation. Allow equipment to dry and move it to the work area.
Find a concrete surface, or a similar level area, that allows plenty of room to work on the mower. Park the lawn mower over the area and set the parking brake. Make sure the mower Power Take Off (PTO) is disengaged. Remove the key from the mower to avoid accidental starts, especially if grandkids are about.
Orient the mower deck in position beside the lawn mower. The front of the mower deck is more round than the back half. In addition, the front contains guide wheels mounted to the deck to prevent scalping the lawn.
Raise the mower level adjustment arms to the highest setting. This will provide clearance under the mower for positioning the deck for installation.
Slide the deck underneath the mower and visually center it between the front and back wheels. It should also rest center of the mower from left to right.
Lower the deck level adjustment arms until they just begin to touch the mower deck. The arms should almost line up with the lift hangers welded to the deck. The lift hangers pin to the lift arms in order to secure the deck to the lift. The deck may require a slight adjustment by hand to line the holes up perfectly.
Insert the pins, attaching the lift arms on the mower to the brackets on the deck. A flat washer and hairpin fit to the end of each pin to hold it in place. With this done, the rear half of the mower deck installation is complete.
Insert the stabilizer bar at the front of the mower deck. The bar is shaped somewhat like an "L". The longest section is already attached to the front of the mower. The short section of the stabilizer will fit into a bracket on the front of the mower. There are several holes to choose from when installing this bracket. The one which best levels the deck from front to back is the proper hole.
Slide the bar into the bracket hole, and secure with a hairpin. With is bar installation complete, the deck is mechanically attached to the mower.
Connect the mower deck's drive belt to the main drive pulley. The pulley mounts to a shaft directly beneath the mower's engine. Install the belt around the pulley by putting slack in the belt. Rotate the belt's idler pulley, located on the mower deck, clockwise away from the belt. This allows slipping the belt around the main pulley. Once the belt is in place, release the idler pulley to put tension back on the drive belt.
Install the belt guard around the main drive pulley. The belt guard pivots on one side and will rotate into place around the main pulley. Secure the guard in place with the hex-head bolt and tighten it with a crescent wrench.
Raise and lower the mower deck a few times while observing its movement. Ensure nothing is binding up, and that the deck moves freely. Re-examine the installation after the first use to make sure all the connections are secure.