On the front of your Toro Personal Pace mower, unplug the spark plug wire from the top of the spark plug. It might be necessary to twist the plug boot clockwise slightly before pulling the boot off the plug.
Lift the rear of the mower, and place a block of wood under each side of the mower. Gently lower the back of the mower onto the wood. This raises the wheels off the ground.
Hold one of the rear wheels, and remove the bolt in the center of the wheel with a socket wrench. Remove the securing bolt from the center of the wheel.
Pull the wheel away from the inner wheel cover, watching for the spacer washer that is between the wheel cover and the wheel. Grab the spacer washer, and set it in a safe place. Repeat for the opposite rear wheel.
Insert the securing bolt through the center of the new rear wheel. Slide the spacer washer over the opposite end of the bolt.
Position the rear wheel onto the inner wheel cover, inserting the end of the securing bolt through the center of the cover. It is necessary to rotate the wheel slightly to engage the teeth on the inside gear on the wheel, with the small gear pinion on the inside wheel cover.
Tighten the securing bolt with the socket wrench once the gear teeth align. Repeat for the opposite rear wheel. Remove the blocks from under the mower, and reconnect the spark plug wire to the top of the spark plug.