I kept my kit list dead simple since we were going to be walking around A LOT. What I usually put on during game days, a light weight battlebelt with all the mag pouches I needed. Water pouch / canteen / hydration pack, and food.
I'm going to emphasize water, and MRE's / food because in all honesty, this is a camping trip pretty well. Assume you don't have access to the facilities and convenience stores. And maybe something to put those items into when going out on patrol, like a buttpack or an assault pack. Something that's light enough to lug around on the field. Keep in mind, this AO is large. Don't overload as we had FOB's in place so that everyone could rest when they needed to.
Pack a few working guns as well. I brought two that I knew would work no matter what happened. And two extras for friends. You are in the middle of a mountain, so get all the working guns together. Test fire it, and make sure they will not fail you.
Pack light, and be aggressive