Well since my secret identity has been revealed, I might as well answer your follow-up questions: /forums/images/graemlins/thumb.gif
1st Gen and 2nd Gen are NOT the same, the wheelwell contours are substantially different, so the boxes I built would not fit into the later model K5's (I tried!)
Also, the overall shape is determined by how many cubic feet of space you need for your driver. In my case, I needed to achieve a "net" volume of 1.0 cubic feet for the JL Audio 10W3. "Net" is the volume left after subtracting the driver displacement, port displacement, and thickness of box materials and bracing. I built the box to extend over the tops of the wheelwells because that was the only way to get to my net volume without encroaching on the interior space any further. I still wanted complete functionality of the rear seat, and allow easy, unobstructed access to the seat from the flip-forward front seat.
Those boxes met my objectives. Trying to fit 12's will be tough....that's what I had originally hoped to squeeze in there, but I couldn't get the space I wanted. The magnet depth becomes an issue on angled boxes as well.....
Lots to think about.... /forums/images/graemlins/deal.gif