I am in a similar situation. I currently have 860's and I am noticing some sag. Add the weight of the front bumper, winch, skid plates, rockers, rear bumper w/spare on swing out, up to three jerry cans on swing out, roof rack and drawers, then add in 3-4 adults and all the other crap, I am thinking that the 860's just aren't enough, and I can tell when I hear a crunch sound on the trail. Since most of the items stay on the truck, I am thinking that 864's are the way to go. Looks like a fairly easy job, any suggestions?