try building the box directly in too the back seat. you could do this by fabricating a new back seat out af MDF and cut 3 holes in it for the subs then use a grill to pro tect your subs. you would need to build the actual box of of the MDF for the seat in to the trunk. then have it upholstered, you could probably use the old upholstery and have it port in to the trunk. this would give you a sweet looking set up with the subs firering into the interior of the car. don't ask me about the port tuning and dimentions of it the dimentions you will probably have to figure out your self. if you do use this design send me some pics. or post them.

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