The great sacs data is my home water your idea of fishing around that cluster of islands is s great place to start. You will find many rock piles and underwater old foundations and stone walls. There are also allot of drop offs etc. in the middle of those islands is basically a big flat of shallower water. Another great location is the south east section of the lake. Allot of big northerspns over there. The majority of northerners are caught thru the ice. I routinely catch. 40+ inch females in March. I would concentrate on shallower waters in the early am then work out to deeper water as the sun comes up. What kind of technique are you thinking?