When using dry ice for transport, I made a plywood shelf for each ice chest that fits on the inside lip in the ice chests. Cut a few 1.5" holes with a holesaw, sand, and finish with 2-4 coats of polyurethane. After I pack the meat. I put in the shelf, and put dry ice on the shelf (wrapped in newspaper). I have hauled meat from Colorado (850 miles), and Wyoming (1,200) miles using both methods without any meat spoilage, and without having to add any extra dry ice. Sometimes, I do have to drain and add a couple of extra blocks if I am using the "wet" method.