2014 Dodge Ram Fifth Wheel Prep Option?

.....I still may can my picture frame adapter and go with the drop in ball and Andersen ultimate hitch...so much ligher in weight and so much easier to mess with....looking back now, wished I had gone this route.

I have spent time on Anderson's website and even watched the video where the hitch was crushed by a huge press at 50,000+ pounds. All in all pretty impressive. The one thing I am trying to get my head around is how much pressure does the base of the hitch put on the truck's sheet metal bed and if little or no pressure is applied then how does the base of the hitch not move around? I guess I need to see one in operation and the answer would be easy to see. I realize it goes into the GN, and the base is just there for support. But, still there must be some weight on the base and therefore the sheet metal of the bed. Am I visualizing this wrongly?