It's very difficult to find information like this anywhere, so here comes another question (apparently I'm the first to think of these things -- that or it's a bad idea

)...
Is it possible, since its current design is giving me all kinds of rattles from a pretty loose fit, to design a custom rear deck / package tray for my 6x9s, complete with a sealed enclosure? What material would you use for this and should I do it myself if I'm a complete fabrication newbie? (note that I do learn VERY quickly

)
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