Patman, that is a really good idea for the box build.
What have you decided to make the box out of? MDF or fiberglass? Use LIQUID NAILS. Works great and provides a good seal after the box is built.
I built a small box for one 12" Pioneer under the bench and it worked out pretty well. Getting the individual seats and building the box in between is a great idea. Where did you get the seats from? I might have to rethink my set up.
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