1. Do not let anything rub the bottoms or sides of your tanks. They will wear through.
2. Why not glue the panels under the slide-out area?
3. Remove the antenna, leave the mount. You find a better place to run the solar wiring (unobtrusive) like down a vent pipe or through one of these:
https://www.amazon.com/Waterproof-Restmo-Weather-Resistant-Housing/dp/B07WL7D9V6/ref=sr_1_2?dchild=1&keywords=rv+roof+solar+parts&qid=1599500163&sr=8-2
Oh....and yes. You should locate the roof trusses to screw in the windward mounting brackets.
