When I smoke fish. Brine brine brine. If you dont. Dries out very quickly and you normally end up with jerky.
Living in Michigan I catch a ton of salmon and steelhead. After brining the fishing you need to remove from brine. Pat dry. And let it air dry on rack for a couple of hours. Brine preserves the fish. So don't worry about spoilage. The fish's surface will develop a sticky touch to it. Then you are ready to smoke. You wanna smoke at a very low temp. Like 175 to 200.
I prefer to fillet them. Some people cut the fish in large chunks. Up to you really.
A bunch of steelhead I got last year.
Me with a ton of Kings I caught
My good buddy with a nice King