First your pics are too big. Next you have to follow the back bone all the way through. It's much easier to use an electric knife.
Go down just behind the gill plates and turn it when you hit the back bone and work it back and forth through the entire fish until you hit the tail,. then flip it over and start at the tail where you stopped and scraping the skin take it all off.
Used a regular knife for year and did thousands of fish when I was guiding, but an electric knife is so much easier. Oh and do the side with the fish belly facing you first that will make the other side easier.
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