Parker,

The trophy rainbow fishery on the Kenai takes place from the outflow of Kenai lake, down to about the Russian river confluence. Cooper's landing is right there, and there are many places to go in and get specific info on what flies to use, places to fish etc... I'm not sure what kind of water you will encounter in that stretch of river, but hopefully your cousin is relatively experienced at rowing his raft. The "Fly fishing only" regs for reds in the upper Kenai mean that you can only use flies with a certain hook gap size. (coho flies are what everyone uses). You won't see too many people actually "Fly fishing" up there. Some people use flyrods with mono, but everyone uses weight of some sort to get the fly down to "line" those reds. The rainbow fishery is a different story. There are some big beautiful rainbows up there running anywhere from about 14" to about 12 or 13lbs. I believe. If you had a quality 6 or 7wt. setup, you will probably be ok. I haven't had too many chances to catch one of the big rainbows, but from what I hear, they tear it up pretty good. My advice would be to use your gear rod rigged with the coho fly and lead to flip for the reds at the Russian confluence, and for the rainbows, stop in to one of the outfitter offices/stores along the highway, and get dialed in on the exact flyfishing techniques.

Good luck to you and Kid Sauk,

Mark