First post here. I've got a 2001 Forester I've had for a couple years now. Plenty of miles and love. I've finally decided to install an audio system. I'm currently planning to convert the rear cushion into a fiberglass enclosure that will still function as a seat. I want to put two JL W3 10" shallow mount woofers. Does anyone have any experience doing this? I roughly have the airspace figured out and how to lay the matting and resin. What I can't figure out exactly is what the framework of the seat is like. I have purchased a salvaged rear cushion for trial and error. How do I lay the upper portion of the enclosure? I was thinking I would determine the placement of my speaker rings, cut a recessed hole deep enough that the woofer and grille will clear the floor, and lay my fiberglass so it exceeds the area needed for the box. Then, I would cut out the area needed for the upper portion of the box, lay the matting, exceed the area needed again, giving me a lip on each, then marry the two using more resin. Will this work? Whats the easiest way to cut the foam out cleanly?