UNless you're competing in a DB drag or some form of competition, those subs are pretty much useless. There's no way you can use their full potential in such a small car. They will overpower everything else untill all you hear is bass. Large woofer = bad response time.
Kick them out and get a good quality 10" woofer. I have an JL audio one and you can hear me coming 5 blocks down if I crank that mother up.
Oh, and I can still put 2 large grocery bags and a case of beer in the back as well.
You might want to remove the content listing from the back.
No use in a stealth install only to tell thieves what's inside.