whitefish chain of lakes……..lake trout??

I am spending a fair amount of time this summer up on the whitefish chain (at the cabin) and have read a little bit on lake trout in the chain. after a little more research on lakers up there I am not finding much info on people fishing them up there. last weekend I saw a boat at a restaurant on the chain and a few of the rods in his boat looked a lot like trolling set ups for lakers. is there anyone on here willing to share any info on fishing for them up there? I know a little about lakers and how to fish them but wasn’t sure if there was any special tricks. I do not have any down riggers but have pondered the idea of getting one so