I also removed my seat and then the weather stripping and the sill plate. I then used a long flat screwdriver to reach in and snap the clips loose. After getting everything changed out and put back together, I couldn't tell a whole lot of difference in the sound. The design of the rear seat pretty much blocks most of the sound of the rear speakers. I should have just saved my money and left the stockers, since my front components fill the cab pretty well. Go out to your truck and run the radio with the fade set to the rear speakers and you will see what I mean. Just my $.02
Roger