Need help designing an SPL/daily box

[Lucky4Designs]

My Sundown SA-8D2 should be coming in sometime this week, I've been hearing about a lot of different sizes and tuning frequencies that work perfect for this sub, but I am not working with a whole lot of space! I am wanting to build around 0.8 cft^3 @ 34hz, but it's going to be impossible to get that from a box that's built under the rear seat. I'd like to be able to get the most SPL possible out of this box, but still be stable enough to be a daily driver. I've heard of these things outbeating 12's with a single 8" so I'd like to be able to turn some heads

My initial thought was to build it between the front and rear seats. Not whole lot of people ride in the back seat anyway (May do an SA-8 wall back there after it's paid off) so box depth isn't really an issue. Keep in mind the draw-up is just a rough sketch of what I'm looking for. I've already taken into account the displacement of the port and the bracing and it will put me around 0.84 cft^3 @ 34.67hz (according to REAudio's box calculator) and in another forum, a guy claimed to achieve 147.3 dB's on 600w RMS with an enclosure very similiar to the one I designed.

As you can see, I don't have an issue so much with length. Mostly with height and depth and the angle of recline the front seat will have. I have seen how far these 8's can throw, and I definitely don't want the cone slapping on the seat. Sundown recommends that there's at least 2 inches between the bottom of the box and the bottom plate of the motor.

Here's my rough drawing of what I was thinking. I'm just getting a tad tired of coming up with design after design and nothing ending up working, and I finally thought of this one. Simple, yet effective?

Any comments/suggestions? I'm looking to get this done pretty soon, haven't had beats in over a year!