try phoning the shops up there. Or call some of the shops down here and see if all the info matches up. Most important check out your Fly Lines and Rod to see if you can do this type of Big Water fly fishing. I just got back from the Thompson and was suprised how my Skagit technique did nothing for me. Big Fast water frustrates the lake fly angler. Also test your leaders and tippets. Those big boys will toy with you.
Just shy of adding split shot to your leader, Skagit lines are the most effective way to fish the Skeena. They will hurl 1/2 a chicken and 15' of T-14 a long way........
You will miss the majority of the springs and sockeye, but steelhead fishing will be on fire, as well as some good coho fishing.
black,blue,purple,pink,chartreuse........any of these colors, in any combination, tied in an "intruder" pattern, fished on a tip suited to the water you are on, will produce well