Since I kept the sevengiller I caught at Rangitata, I decided to preserve the jaws. Cutting them out is fairly easy, just getting all the meat off them is harder, and can take several hours. Once you’ve got all the meat off, you’re meant to soak them in bleach for a couple hours, then leave out to dry.
I stuffed mine up by leaving them out too long in the sun, and they sort of shriveled up and went out of shape. So just remember not to leave them out in the sun, but more in a shaded area.