For whatever it's worth when I lived in Western Mass I fished out of Gate 8 on Quabbin Res. which gives up quite a few big lakers (10-17 pounds annually). Two methods were used
1. Still fishing with big live bait
2. Slow trolling with big bait (6"-10") Golden shiners with a Davis rig or big dodger.
Keep in mind Quabbin doesn't have forage base of smelt Winni does.

Dean

Reel it in --- I was doing something similar, marking deep fish that were likely lakers, then putting my presentations right in their face. After I got the hang of it I didn't need to pop the releases -- the togue would do that for me! They're not salmon, but put up a nice fight and taste great if you smoke them
-Eric

In 04 while I was on Sabago, I found some huge fish suspended 140 feet down over 250 feet. I was using silver/blue flash kings and had about a 10 foot lead off the balls. Hooked up 18 of them just trolling through them at 1.5, all between 6-13 pounds the first day. Everyone else was in 50'fishing. It was the middle of July.
Did this for the week I was there, over 60 lakers all good size. Had the fish biologist there checking fish that week, they came out with me the last 2 days and had a ball. Biggest being 2 @ just over 13lbs.

Popeye

Gotta get deep. I was reluctant to go too deep at first...but caught the biggest togue at 86-ft...and then bottom!

-Eric

I got a king one year up to Ontario 185' down over 200. Champlain is another lake you can get some big lakers in by going "down on them"

Popeye

Trust your sonar, hope you can trust your GPS maps, and prepare to raise the ball in a hurry...!