Our cages are very similar to Hals'. To make them round we overlapped one square of the wire and used small hog(nose) rings to hold them together. I think the rings were called shoat rings, similar in size to the ones Dennis Rodman wears.
We cut the bottom wire also to form legs, but found they still blew over in the wind. Now I add two electric fence posts to each cage that are driven in about a foot deep. I use fence insulators to secure the posts to the cage.
They work pretty well but some ripe fruit can be hard to see, and they consume quite a lot of storage room.