A lot of this takes common sense, if a lance 11' camper weighs --#'s, and that weight with the truck weight maxes out the E tires, guess what?, gotta go beefier. . My 245 70R 19. 5" Michelin XDE-MS 12 ply F rated is set at 4080 # @ 95 psi... these would do wonders for a swr camper.
Eric,
I have weighed our truck and camper combination on commercial truck scales. We are over the GVWR, but well below the GAWR on both the front and rear axles according to "the little sticker on the driver's door jamb". With our dually, wheel/tire upgrades aren't necessary.

Bill