Assuming I put the hounds at maximum height where is a good height for the upper diamond mounts to avoid the diamond wires touching the stays during mast rotation ?
Unfortunately you can't even assume that much!
The general rule is that if you are carrying a heavy crew then you should put the hounds high to give the top of the mast the most support. If you are light you would set the hounds lower to allow the mast top to flex more and depower the main more easily.
I am a light-to-middle-weight cat-rigged sailor (72kg) and my hounds are right in the middle of the allowed range. This setup was also used by Chris Boag sloop rigged, with a very light crew - they couldn't have been more than 115kg combined. I hope that helps!
As far as binding on the sidestays is concerned, the position of the diamond attachments fore-and-aft will also affect whether they catch.
Tee-balls are stainless fittings which are pressed on to the end of the wire. They just hang in a reinforced hole in the side of the mast, and are easily removable from the mast. You have to find a rigger/chandler with the hydraulic press to make them up, and the fittings are not cheap.
