My friend wants to replace the speakers in his '98 mustang GT and I checked crutchfield and they said that the front and rear take 6x8s so I checked out their options and I'm looking at the Pioneer 6x8s. One pair is 3 way and the other pair is 4 way. Should I get two sets of 4 ways or make one set 3 way and the other 4 way? What configuration would be best? Or 2 way all around? Need some help, always get confused with the different "2-3-4 ways"