I was watching a You Tube video and this guy was working on a Walleye. During his instruction he mentioned that back in the day he would skin a fish/sew the incision and then fill it with wet sand. I would assume once it was dry he would empty the sand and then fill it with fish fill or something. To me if it was packed tight it seems like it would retain its shape. Just wondering if anyone ever tried this and how did it work out?