before i start to explain i get to make something clear first so i don't feel like a dumb ***.. the 3 way i meant has a pair of tweeters, a pair mid and a pair of woofers.
in most cases you have to build a kick panel for the woofers if mid's going into the door and tweets in the dash or whatever.
you want the kick panel to be professionally done so that the sound stage is at the optimum level. make sense?