hi guys .....in the back door of my disco is a little sub box thing and I fancy trying to get it to work but all the rubber has perished on one of the little subs.....so 2 quessies.....were do i get a new speaker or a new unit....and 2....how do you wire the thing up do you need a factory head unit or can it be wired seperately.....Cheers....Rog...xx