you knw how you can get the factory sub, well i was thinking of gettin a custom setup but hidding the subs on each side, running about 500 watts on each side, the only component im missing is the enclosure, any ideas?

 

build it out of mdf is all I can think, whys this in the xb section though?

 

If you want the subs hidden and stealth, pull out the rear paneling, tape up the inside area for the enclosure real well and make a fiberglass mold of the fender area. Fiberglass resin does not stick to wax paper, tin foil, etc., so using pieces of this in the backing of the fender will make the mold much easier to remove when it has dried. Remove the mold from the car, reinforce the heck out of it with several more layers of fiberglass. Shape and add the front baffle of your choice... MDF, more fiberglass, etc.. You will want to get a good idea of the exact volume of the enclosure you are making. It would be best to optimize the enclosure volume to whatever choice of subs you choose.
I know this is a crude DIY lacking much detail, but you get the idea.

 

FG is the way to go, though it's not entirely hidden or "stealthed" it will be the best way and gives the most when trying to fit it in whilest not loosing alot of room.