I recommend brining. I smoke the salmon on the top rack of the bandera at about 200- 225 degrees. I do not cook it very long. I generally watch it pretty closely. Not like other things that you close the smoker and let go for long periods. I like a brown sugar brine (good to add some jalapeno powder to the brine). This gives the outside a sweet taste and insite is moist. It is easy to over cook.
Good luck! Stan