Unplug the GE dishwasher before you start. Never attempt any repairs or parts replacement without first unplugging the appliance.
Remove the lower dish rack from the dishwasher and set it aside. Use a screwdriver to remove the screws that hold the access panel in place. Remove the screws that hold the drainage hoses in place, then disconnect the wires from the drain solenoid and the motor assembly. You can simply pull on the wires to disconnect them.
Loosen but do not remove the clamps that hold the motor assembly in place. Remove the motor assembly from the dishwasher. Hold the motor shaft and remove and discard the cutter blade. Rotate the grater clockwise, then remove and discard it.
Remove the wear ring and discard it. Hold the fan, turn the impeller counterclockwise, then remove and discard it.
Remove the old bellows seal and discard it. Insert the new bellows seal, then reverse the above steps to reassemble the dishwasher.