Don't put 8's in the rear. You'll introduce a comb filter effect and it won't be worth the trouble. If your heart is set on 8's, they need to go up front. If the mmats is a 2 channel you could run it to a pair of 8's and bridge the kicker to your component set. lowpass the sub around 80-90hz and run the 8's from about 80 up to around 200hz and your comps can take over from there.