My advice would be to find a rock or sand bar in the middle and fish where the current breaks at the head and tail of it. Punch holes in various depths and keep your bait 6-10" off bottom no higher. The eyes usually try to make their way to the shallowest part come dark. Think drop shotting for the big ones theres many different ways and Mr Marty stated one of them, a collapsible tent pole might work well for such situation. You may be able to locate or make your own line pinch like on a planer board. Here is the method to my madness.
Use only enough weight to keep the set line tight and still release the other line. The weight should be placed on bottom unlike trolling.
If that doesn't work consider jigging for them with several different lures. Be safe is the number one goal.
Fishassin