I did something similar to your idea. I used the same hooks, but instead of the wood, which I did not think of, I used the center section of a two inch wide metal curtain rod that I had. My sleeve is loose enough to put the rod in, and still allow the hooks to grab the existing curved edge of the rod. It did stay on the wall the day my cat Bruno tried to sharpen his claws on it, and got stuck hanging from it until I rescued him. (He has not tried that since...lol.)