In our 320 the fridge sits above a pretty good sized open cabinet. This cabinet has two doors on the front, no shelves or pull-out tray -- just a big opening that is hard to access.
I decided I could make it more user friendly for my wife by installing a sliding pull-out tray. I have never made anything like this so it was all new to me. I also decided that it would be nearly impossible for me to reach inside and attached drawer glides. So I decided to build my tray outside of the cabient. I cut a piece of 3/4 inch birch plywood that was about two inches shorter one each side and one inch shorter than the front to back measurement. It was on this plywood base that I built my sliding tray. I used two bottom mount glides.
If I had it to do all over again, I would have made the side to side measurement about 1/4 of an inch shorter. Then I could have easily stood 12 ounce cans of soda on each side. I can only stand cans upright on one side and have to lay them on their sides to the left of the tray.
Once the tray was built, all I had to do was slide it in place and anchor it with four 1 and 1/4 inch drywall screws. I pre-drilled each hole and reamed the hole so that the screws would be counter sunk.
The tray was finished with 3 coats of polyurethane for protection.
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