I'm a bit perplex removing this Yale door knob. There're no screws on the inside knob and no slot nor retaining screw. I see a little tab that looks like it's part of the interior ring. I tried pushing or pulling on the ring but still can't get the door knob out. Can someone help? Do I need to have the key in as part of of the disassembling process? I was expecting to eventually see two long interior bolts that hold the outside and inside piece together. Thanks.