37Z

I built a fiberglass sub box and false floor located between the rear shock tower brace and the space tire space. It houses an 8" sub, signal processor, and 5-channel amp so it is all out-of-sight. A 6.5" or 7" HU with nav will fit in the stock double din space (I had a Kenwood in my Z). Best to add new speaker wires instead of using the stock speaker wires (see SikNik sticky for details). If you Z is with a manual transmission, you can install a power wire by removing the rubber plug located behide the battery to the rear hatch area to the amp. Pricewise, budget a $2-3K for a good sound system.

Good luck!