I have a couple sets now.
My first set was mounted on an angle iron that was carriage bolted to the house.
This angle iron was basically for the bottom, also ran 2 pieces up the back side and had another piece on the top of the panels bolted and later tack welded.
Forms a 45 degree with the top part of the angle iron across the top acting as a bracket/brace.
It held up very well through all last year's rain, sleet, snow, and some pretty high winds.
The angle iron was free; shipping crate stuff and I believe 1/4", merely painted for weather protection.
The mounting stuff they sent when latched together and all the panels on it , it does become pretty stable. I didn't like the angle and because of trees had to get it up much higher, without being on the roof.
Once I get a non-rainy weekend :-O I'll be reinstalling it up there with the "city approved" second set.
I too am not using the "box" as a controller, but noting more than another PDU, Power Distribution Unit.
Ghurd's controller can also be used as a LVD :-) I don't have mine dialed in yet, work keeps getting in the way :-/
Hope this helps;
Bruce S