The vibes come with in-line crossovers so its just a case of wiring them up correctly, the speaker wire go's into the crossover and 4 wires come out the other side. The only thing you may have to do is extend the wires for the tweeter or midrange depending on how far they are apart (one in the dash and the other in the door e.c.t), I had them in the front of my last car and when I get round to it they'll be going in this one. I'm gonna fit them as coaxial and in time mite be moving the tweeters into the round plastic button's that blank off the window winder holes, I thought about putting the tweeters in the dash and the mids in the door's but to me that seems too far apart (could be wrong though !). Then I'm just gonna put my sub in the boot and see how it all sounds, I also thought about having two pairs of coaxial's in the front, in my previous golf I just had the dash mounted speakers as there were none in the doors. I would be interested to see if anyone has fitted two separate pairs in the front and what they sound like !