If you are handy with tools it's a challenge but doable. I don't remember exactly but it probably took me a day to install the four `Arms'.
Do they help movement? Yes
Do they eliminate all movement? No
Are they worth the investment in money and labor? Yes
But you would expect me to say that because I have already spent the money and time.
Are they perfect? No. Since they are located in a nasty area that gets lots of road moisture, salt, dirt, etc. they steel parts can get rusty and after a couple of years I have had to replace some of the movable parts. Also the Tee handles rust. I would like the option of stainless steel rotation parts but that's probably out of the financial question.
If I was to do it again I would spray Corrosion X or similar preventative on all parts frequently.