Open and lower the dishwasher door to pull out the upper rack halfway from inside the appliance.
Grip the plastic cap on the end of the left rail and twist it inward, to the right, to unlock the old rack stop. Pull the part straight out of the metal rack glide.
Remove the old rack stop on the right side by twisting the plastic cap inward, to the left. Pull the part out of the metal glide.
Insert the new rack stops into the ends of the metal glides st the arrow on the rack stop's cap points inward.
Bend the cap on the left rail to the left to snap it in the locked position. Bend the cap on the right rail to the right to snap it in place.
Push the upper rack into the Whirlpool. Raise and close the door.