Yes you need it because it holds up the fridge cabinet. My panel was cut to the depth of my fridge, just short of the thickness of the fridge door so the doors could easily open and close. I hope these pictures explain what should occur. Yes the panel will extend out further than your cabinets, but this conceals the black sides of your fridge. I didn't want to pay the extra cost for a counter depth fridge and am quite happy with the final installation.
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