To work on the drum or any other component in a Whirlpool Thin Twin washer, you will need to remove the front panel. Unlike standard cabinets washers, the top panel of the Thin Twin will need to come off to access the front panel retaining screws. The piece of metal between the bottom of the dryer and the top rear of the washer is the key to removing the rest of the washer cabinet.
Unplug the Whirlpool Thin Twin washer/dryer combo from the wall electrical outlet. Remove the three screws that secure the angled transition panel to the bottom of the dryer with a Phillips-head screwdriver. The screws are at the bottom front edge of the dryer portion of your unit. Allow the top of the transition panel to come down and lift it away from the unit.
Insert a large flat-head screwdriver into the two rear retainer clips in the top panel of the washer. Pry the retaining clips out of the washer top and slide the top towards you and away from the unit.
Remove the two screws that secure the front panel to the panel brace with a Phillips-head screwdriver. The screws and the edge of the brace are on the top edge of the front panel. Lift the brace away and lift the front panel away from the washer.