Wicker storage bench tend to be a bit more brittle, and they will have to be made to prevent crushing your favorite piece reinforcements. A few cuts to a sheet of plywood and a couple of screws are all you need to turn your trunk into a bank, and still maintain storage. Your trunk will be tough enough for adults, even at full maturity to sit comfortably. Measure the inside of the trunk. Measure the sides from top to bottom and from side to side. If the sides are tilted in the direction of the bottom, get the measurement from side to side at the bottom, too.
Measure the inside of the top, side by side and front to back. If the top has an edge or lip, measure the depth of that too. Cut two pieces of de-inch plywood in the size and shape of the inside of the sides of your trunk. Add the depth of the upper part of the trunk to the height of the pieces, minus ¾ inches from the top of plywood will add. Use a jigsaw to make cuts. Slide in to make sure they fit correctly without forcing. Make the necessary adjustments.
Cut a piece of de-inch plywood for the interior dimensions of the upper trunk. Set this piece inside the top to make sure it fits without forcing. Make the necessary adjustments. Cut a rectangular 4 x 1 inch slot in the center of the top piece. Make the 4-inch side of the slot parallel to the trunk width. This is used as a handle. Pilot holes along both side edges of the top piece with a 1/8 inch wood wick. Frames 3/8 of an inch from the edge. Make at least four holes, spaced evenly along each edge.