I couldnt do it all by myself for the first time but then tried with a friend finally and got the Infinities Reference 9603i pair installed in the back of my Civic sedan. It was the first time and a good learning experience. Also...i realized how much mis-information there is on HAN Most folks over here said that the whole rear needs to come off which as a matter of fact not true at all. I am not suggesting that it was on purpose but i guess there is always a better way.

Here is the DIY:

1) Fold the rear seats down
2) You now have to take out the side seat cushion (the side part which stays when you push the rear seats down)
3) There is a 10 or 12 mm bolt right underneath the bottom of the side cushion at each side which needs to come out. You will need to pass a socket extension b/w the side and bottom seat cusion as it is kinda deep inside bolted to the frame.
4) Once unbolted, push the side cusion upward. It will simply pop out as it is held with a clip on the top side. Remove the other side also.
5) THERE IS NO NEED TO TAKE OUT THE BOTTOM SEAT CUSION OR EVEN THE SIDE PANELS ON THE INSIDE. LOTS OF FOLKS SAID THAT THIS NEEDS TO BE DONE BUT IT IS NOT TRUE AT ALL.
6) Disconnect the third brake light and pop out the key hole trim from the rear dash trim.
7) The rear dash cover is held on by clips only. Carefully push it upward and towards the rear window...it will pop out easily. Dont use alot of force as you might break the clips.
8) Now unscrew those ugly 15W stockies out by removing four philips screws. Make sure you unplug the harness first from inside the trunk.
9) Install your new speakers by placing them in the hole carefully. Align the speaker holes with the holes in the frame. I suggest you use the stock screws as they are a better fit. (Against popular belief, my Infinities were a perfect fit and they are also not anywhere close to the trunk rod....even though they are twice as deep compared the stockies)
10) Test the speakers.
11) Reverse the process to put everything back on.

Upon testing, i noticed that the speakers were too powerful for my Sony Xplod Head Unit (52x4). My friend suggested that i install an amplifier to get the right amount of juice out of the infinities...so this suggests that to get sound...you need to have the right combo. I turned up the volume on the deck and beyond a certain point....the highs were getting distorted.

I was earlier thinking of two options...Rockford Fosgate or MTX thunder. My friend adviced (His opinion only) that RF is better for subwoofers while MTX is a better choice for internal speakers. I am kinda new to all this so i would like to ask all of you guys to tell me whats best.

Also...i read reviews about the 9603i that if you have a good amp...you really need a sub with them. My front speakers are still stock 6.5 and i am thinking of upgrading them also. Any suggestions on the amp guys?

Hope this will be helpful.