Just entering into ULF territory I immediately needed to find a method for moving about with all this much larger gear.
I found a messenger bag that is 3000cu. inches, waterproof, and very comfortable, the only modification I made was some light padding.
http://www.chromebags.com This bag will hold six 11x14 holders and my folded Phillips explorer if necessary a set of straps on the bottom will hold my tripod and head if I have to do any serious hump'n.
I keep all my immediate necessities on a Lowpro S&F utiliy belt such as water, meter, loupe........this way I never have to set anything on the ground.
My whole system, tripod and camera is for the most part is carried on my shoulder, leaving more room in the bag for additional film holders.