I just changed out the four 5x7 speakers that came with my Shaker 500 with some pioneer 3 way, rear and 4 way, front. All I can say is what a difference in the sound. The rear deck speakers are the exact same as the ones in my F150 with the basic sound system, cheap.
I have couple of obsevations/complaints about how Ford designed things though. First could they have put the rear speakers any futher back, you only have about 2" between the window and the screw. Second, Ford put 9 screws and 2 bolts to hold the front door skin on. My F150 has 3 screws and 2 bolts, which you dont have to remove to change the speaker, just pop a panel.
I have couple of obsevations/complaints about how Ford designed things though. First could they have put the rear speakers any futher back, you only have about 2" between the window and the screw. Second, Ford put 9 screws and 2 bolts to hold the front door skin on. My F150 has 3 screws and 2 bolts, which you dont have to remove to change the speaker, just pop a panel.