Installation guide for Infinite 6020CS speakers?

There is really nothing special. The biggest headache is the fact that the stock speakers are riveted in. You will need adapter plates to install the speakers in the stock locations. Here is a step by step:

Front door panels (rear is the same minus the sail panels):

1) Remove the sail panel/tweeter pod by pulling it away from the door. There 2 clip holding it on. Unhook the tweeter wiring.
2) Remove the finger pull cup screw and the finger pull cup from the armrest.
3) Push up on the window switch bezel through the finger pull cup hole and pop out the switch bezel. Disconnect the wiring. Note: you will have to reprogram the auto window on the drivers side if you disconnect the drivers side switch, there are instructions on the forum on how to do this. You can avoid this by removing the drivers switch assembly from the bezel and leaving the wiring attached while you work on the door.
4) Pull the chrome door handle out and remove the small plastic panel that is behind the chrome handle. Remove the screw that is behind the plastic panel.
5) Starting at the lower front of the door panel, firmly pull the panel off of the door. Once all the clips are disconnected lift the door panel up and off the door and then disconnect the puddle light.
6) Drill out the 3 rivets (3/16" drill seems to work well), remove the old speaker, and remove any old rivet bits from inside the door.
7) Run the speaker wiring adaptor (or splice in new wires) from the factory speaker connector into the door through the speaker opening.
8) Attach the new speaker adaptor plate with screws or rivets (3/16" pop rivets with backer washers work well) making sure to not crush the new wiring. You may need to notch the speaker adaptor plate for the new wiring.
9) Attach the new wiring to the new speaker and then attach the new speaker to the adaptor plate.
10) Reassemble door in opposite order.