I got the Infinity 8602's installed the other day, big difference in sound over the factory set up. They have a lot more punch with same volume and much deeper, clearer sound across the range.
Very happy so far, I have taken several trips around the block toying with the tone set up.
Install was pretty easy, it helps to have two people to manuever the door panels, mostly for replacement. My buddy helping me had done some car stereo speakers before so it was nice to have him showing me where to pry etc. The only speciality tools required was 5.5mm socket for the screws on the speakers. It took us about 1 hour to get all 4 speakers intalled.
The people at Crutchfield were very helpful, I got the Ford adaptor wires so everything was plug and play. I might do a Sub-Woofer next but waiting to get more seat time with my current set up.
Over and out