From what I can remember (it's been a while since I've paid attention) but I think the l7s like ported boxes better than sealed and you would just want to find one that has the correct volume and frequency tuning that the sub is designed for. The box is everything. You could have a $50 sub in a proper box and it would sound better than a $700 sub in a box that is not sufficient

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2003 Reg cab, short bed, 2.3L/5 speed