In my case, the shank nut tightens against the inside surface of the metal door panel. I needed a larger hole to be able to tighten the nut (and install the lockwasher).
You can also see the plywood rings that I used to stiffen the shanks. I didn't want to remove the liner, it has shelves that are useful to me. But I also didn't want to tighten against the door liner, it is too compressible. And I really didn't want the shanks to be able to rotate once mounted. With this method, the shanks can be torqued plenty tight. And I get to keep my shelves.
You can also see the plywood rings that I used to stiffen the shanks. I didn't want to remove the liner, it has shelves that are useful to me. But I also didn't want to tighten against the door liner, it is too compressible. And I really didn't want the shanks to be able to rotate once mounted. With this method, the shanks can be torqued plenty tight. And I get to keep my shelves.