If you check past posts you'll see many mods some of us have done. Since we don't have a new rig I'm not sure what will apply but some things I would check are. First, check your furnace return air vents, if the wind is blowing you may find it's like a furnace was on (take the vent out and block it with foam board until winter). Second, in the areas where you want more cool take the supply vents down and cut every other slat off and while you're up there you'll probably find that the holder it's attached to protruds into the vent blocking flow (cut it back to even with the duct). Third check the vent over your stove, on our HC when the wind is blowing the hot air comes right back thru the vent (not so much on our Montana) I lock the vent cover when not in use (it's a PETA but when the temps are near 100 it's got to be done.
Dick, Joyce, Diego, Picatso and Gustav
2017 3720 RL, and 2013 HC 343RL
2017 3500 Dodge Maxi DRW 4X4, Pullrite Hitch, IS, Disk Brakes, 3rd AC, Winegard Traveler, Bathroom door mod, Dometic 320, couch for desk swap, etc.