You can use the ridge that the latch attaches to as part of the key structure. There is also a J-shaped structure inside the plug that would function as a key

You can use the ridge that the latch attaches to as part of the key structure. There is also a J-shaped structure inside the plug that would function as a key as well, prevents the plug from starting when rotated 180 degrees. == ------ | | | | / | ------