As we have cats, we were concerned that they may catch removable parts, and pull them off.
We realize that is unlikely, but still possible. We have clever, and no so clever cats.
So we added two removable sliding 1x2" wood pieces to secure the removable piece at night, or when we are away.
There are L-brackets at the bottom to support and hold them in. The pieces slide in perfectly at the top in the wire overhang.
See the next / previous steps below on this page.