I've always had to keep the fillets whole with a little piece skin attached. I'd freeze up the whole fillets with wax paper in between so I could get them apart later and chop them up into package size pieces when I got to shore. I called the feds to see if there was anyway I could package them in smaller packages while on the water. He said no that they had to be in whole fillets, but he said what he does is score the fillets into the desired size so that he can break them up and vacuum pack them when he gets home. I'm sure a lot of people do this, but I'm kinda slow on the uptick so I thought I'd share.