I’ve solved both of those issues with lessons learned in Panama at the Jungle Survival School (The Coveted Banana Boat Patch)I always wash the entire truck and wax by hand! Back to my old saying about not changing the oil filter when doing an oil change "it's like showering and putting your dirty underwear back on" same thing not washing or not waxing the roof. For the roof I use a wash bonnet and extension pole and to wax I open the sunroof and stand on the seats with my shoes off of course. That way I can get the whole roof really well covered and buffed out.
I'm down with this. I can't see it and neither can anyone else. I do hose it off when I wash the truck. Which I last did in late May ... they call me Mr. Shiny Truck, so you definitely want to follow my lead. LOL
I always stand in the box which allows me to get the back half of the roof and then I stand with one foot on the running boards and one foot on the front tire to reach the front half.