I really appreciated the photos in this thread.
profdant, I don't think you should use duct tape to separate the metals. With the vibration of travel, it will wear through.
Some suggestions:
Fiberglass backsplash material, it's about half a mm thick or so, available in 4 by 8 sheets at the home store.
Flexible but rigid plastic, not visqueen. Pretty much any type, available at specialty stores or possibly the home store.
Rubber washers, one behind each screw. Or you can make your own out of pretty much anything. I have cut them out of milk jugs, or gotten a used inner tube from a tire store. Thin plywood...
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For good fasteners, and the rubber washers, google 'fastener supply' at your location. Or call a professional lumber yard, not Home Depot, and ask them, 'Who is the fastener shop for pros, around here?'
You will be in heaven when you get there. They have so much cool stuff :-)
