With the weight of the dish there is no reason to worry about a specific area being reinforced. Placement when I installed a dish on my class A was determined by the closest I could get to the entertainment center and still be centerline on the coach. I found the job to be straight forward and not hard. Take your time and locate all wiring needed prior to cutting into the roof.
Jake my sidekick (yellow Lab)
2017 RAM 2500 CC 4X4 Cummins Diesel
2016 Flagstaff 26 FKWS
AF&AM of Idaho