You know how it is when someone gets gung ho about something.Just givin him an option.It can be done.Just a pita.lol, how do you think i feel with this little a** cobalt... lol had to take out back seats to put a ported single sub box in!!! lol, but atleast the back seats got a button and the whole back seat comes out!!! that 18 looks too big in there, the 12's fit perfect, without the trim cutting off half the sub!!! lol my box was 15in tall and 16in clearance, nice little snug fit!!!