Although initially worried when I saw the small box when it arrived I was very happy when we had it fully assembled and up.  Looks fantastic!  When you do this make sure to start with the arms at the bottom of the ball (you'll know what I mean when you have it in front of you) and work up.  Use a small wrench to hold the nut inside while starting to thread by hand from the outside, then tighten with wrench or by hand inside.  Takes a bit of patience to get started and a smaller set of hands wouldn't hurt.  Took about 30 minutes but well, well worth it.