I have never fished Willard but here is a general guideline for gills through the ice that I had from some notes. Hope it helps. ------bluegills will change habits as the season changes. Not adjusting will leave you frusterated or with dinks. The big bluegill tend to gather in small schools, while the dinks who harass you will be found in swarming schools. Bluegill tend to stray into "deeper" water to spend winter. They will hang around close to shoreline ridges or points, near brush and weed beds in 15 to 20 feet of water, if your lake has that depth range. Schools can move onto flats to chase bait and feed, which may be shallower then back deep deep water.
Guess I am a little anal but I keeps stupid little files on locations and where to start fishing on a flash drive.
By anal I mean, I fished a tourney in a the fall with my bro, printed out starting points for prefishing, hit the water and never came with an exact pattern for hitting those spots. But this is what I have from a Bass Pro Ice Seminar I attended many years back! But at least I still have my notes!!
Either way, look for the above features in your lake and use them as a starting point. If you first do not suceed try a move. Sometimes as little as 25 to 30 foot of a change may put you into some fish.
Good Luck and hope this helped a little
