They really want ypu to leave about 1 to 2 inches of skin on the full none zippered fillet. That way they can easily I'd and count fillets to get total count. They accept reciepts for fuel or bait with dayes on them as prof of number of days fished. So keep the tiny paper work, and do the last skin and zipper at home....they will stay fresh that many days. I know it's a pain, but they just don't want the waters over fished.

Or pay to have them cleaned and then they can be zippered and frozen, just have the prof of number of fish they cleaned each day