I cut the thin plastic liner from the rear of the inner fender well, so it was not a cube. The honeycomb you see in the pictures sits about a 1/2" behind the inner fender because their is a bulge in the plastic right where I cut it. The plastic I removed was a flat piece about 3 1/2" wide by 4 1/2" tall on both sides of the truck. It was easier to cut and paint with the wheels off, but you could certainly do it with them still on, if needed.
I used a small Micro Dremel tool from Home Depot with a cutting blade and it took less than 5 minutes.
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