taking the speakers out of the rear is gonna be a b***h.. for me it took two people and about 2 hours.. it was my first time and i f**ked up one of my rear seats.. anyways, you take off the rear seats, then take both rear side panels out (the black plastic), then take off the back side panel and take out the speakers.. hook up the wires.. bla bla.. there are a few things you need like a ratchet, and a flat head philips screwdriver.. sorry i know the instructions are pretty vague (i've got to be getting to school in about 5 minutes), but once you see what's connected to what, you'll get the idea.. good luck with that..
better to pay the $40 to save the trouble and stress.. i got so pissed after i installed it, but i guess its my first time.. next time i'll do better. just make sure you have all the screws taken out, and those tricky black ones you have to break off..