Here is what I have in mind for a DIY project.Buy foam at 1 inch thick or 1 and a quarter thick from an upholstery shop.Have them cut the foam to specific sizes.Say 17 by 14 or something.Then go to a metal shop and buy aluminum panels of same size,again the metal shop will have to cut to size.Then spray adhesive on both sides of foam and panels and glue them together making "a sandwich of panel-foam-panel".You can also spray paint the edge of the foam with black suitable paint,and of course use black aluminum panels to match. Then place them on the shelves and rest various components on them.There are commercial versions of the above concept.
Best
George
Best
George