I used to run the KO's years ago, great for 20k miles them they got hard as a rock and traction went south. Maybe they are better now.The BFG KO3 in 39x13.5r17 would be an obvious choice.
If you really need 38 or 40 inch tires, then that makes sense. Unfortunately that also means I think you're out of luck. Time for earplugs...I used to run the KO's years ago, great for 20k miles them they got hard as a rock and traction went south. Maybe they are better now.
But that said BJG's sidewalls are way to weak for any off road work IMO , Krawlers are the exception.