JL Audio 8w3 with a Zapco ST1 amp. You may be able to go with a Zapco i250.2 amp but its not 2 ohm mono stable and the woofer only comes in dual 4ohm voice coils so you would need to run it at 8 ohm cutting the amp to half power compared to the ST1 which is 2 ohm stable on mono. These amps will give you the power and option to add some more low range without changing the head unit. This is if you want to use the factory space provided and not go more custom. This gear is not cheap and there are reasons for it...you can go cheaper but if I were you I would keep what I have.
Here is a link to a 12w3 install..the ST1amp would work as well but a new head unit would be recommended with 6 volt outputs and sub volume control...not bass but sub out put.
Another with two 10s (non JL) and factory unit