trolling can be effective...
This is example of troll caught hali on Tomic plug (5" 602)..fishing Kings on the deck. I use the green snubbers for the wire to DR ball connection and then run the release clip off the top sampo swivel on the snubber (this gets the lure up off bottom just a bit.
If I am targeting hali on the troll I use an all white HotSpot flasher w lures and BIG herring.
They will also come up a great distance IF they are hungry and if the bait is right. I have seen a 70 taken trolling at 20' in 50' of water...that was something to see in a King hole.
have fun.
JD