I don't see any problems with your set up. Yes, technically your over the 10,000 GVWR that truck carries to dodge certain DOT regulations. You're well withing the truck's actual physical capabilities. The rear axle weight is generally based on the tires, apparently yours are upgraded from what came on it.
I carried my TC on a Chevy 3500 SRW rated for 9,900 pounds GVWR. I weighed in at 11,140 ready to camp. I then carried it on a Chevy dually rated for 11,400 GVWR, I weighed in at 13,000 ready to camp. Both rigs logged thousands of trouble free miles.