I wish I could take credit for this mod but I saw it here years ago. I never got around to it until today. I couldn't store gallon jugs upright in my fridge. Some milk leaked from a jug on its side last weekend and I didn't notice it until today when I was winterizing the PUP. It was a moldy mess. I scrubbed everything out and fixed my bottom shelf. It took about 1/2 hour and some white spray paint. I wish I had done it years ago!