This is a 9' island we did last year with an 18" overhang. We have the wall built in behind the cabinetry and applied cabinet company supplied skins over the wall (beadboard matching rest of cabinetry). We did the base molding around the whole island. The dishwasher in this kitchen is not on one of the ends so we don't have a weak spot at either end. We also have more substantial end panels than it appears you have. You can barely see the black fast caps support bars under the countertop in this photo. They extend out 12" on the overhang side and 12" over the cabinet side.
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18 inch overhang
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