i'm looking to put two 12"kicker L7's in my truck.
would area behind rear seat be enough with sealed box?
also would area Underneath seat be good for 12s?
sure you can run a 1000RMS watt amp with it, but you will not be getting as much out of the sub as it can pump out. with an 18 you will need a Huge box. There IS 5000 watt amps (2500RMS) you can get for not too expensive, just look around. But even then you wont fully be pumping the potential...