I just added an Atlantic Towers arch with solar on the arch. I added 4 150watt panels. The supports for the panels sold by Atlantic Towers didn't work with my panels and new supports were manufactured. Atlantic didn't want to take their supports back, so I have them for sale.
Craig Briggs helped me install the arch...it took 2 1/2 days after a couple of mis-starts. The install is straightforward and clean. I used the supplied backing plates. There is some side-to-side movement which I am so far dealing with when at sea with crossing lines from the arch to the aft cleats. Attaching the arch to the lifelines helps some, but I will probably add removable cables angling from the arch to a pad-eye in the center of the deck below the aft lifeline. I would use them when at sea, and remove them (at least the starboard one) when at anchor or med-moored.