Happy Thanksgiving everyone!Here is an update on my install with details for anyone planning on doing the upgrade.

I've installed an 8" subwoofer, JL 8W7, in a hidden enclosure behind left trunk trim panel.
I've molded the enclosure out of fiberglass. It's bigger than the storage compartment was and goes farther over the wheel well. Volume of the enclosure is around 20 liters and I used pillow filling inside the box to compensate for around 20% or so of volume, since JL recommends 24.8 L. I glued sound deadening material(carpet-like) to all outside surface of the box to keep it from rattling. I don't have any pictures of the enlosure still out of the car, since I only started taking pictures when everything was done except for rear door speakers. With this sub, I can have as much bass as I can stand and a lot more
I also protected the sub from moving objects in the trunk with an aluminum sub grill. The sub was connected directly to the amp with a 12 gauge twisted cable.
Amp is Eclipse PA-5532 5 channel 960 watt. I ran speaker level cables to it from the back of the Nav radio (you can see those going into the amp on the right side of it in the picture).
I routed the speaker cables under the right side sills/carpet. Speaker cables coming out of the amp are going back behind the radio to use original speaker wiring to drive the speakers. It looks like oem speaker cable is 16 gauge, so it should be enough. My original radio was standard, then I upgraded Nav. So, my speakers were wired directly to the radio. If you have an amp in your car, your speaker output wires from the new amp will have to go where your old amp is instead of back to where the radio is. Then I ran 4 gauge power cable for the amp on the left side of the car to the battery. For ground, I also used 4 gauge cable and grounded it to on of the bolts under rear seats. I used monster cable amp install kit as well as speaker wires.
I upgraded speakers to component 2-way MB Quart RCE-216.
Old speakers vs new: 
They come with a midrange 6.5 speaker, a tweeter, and a crossover. For the front doors, I mounted the tweeters in the original location next to the side-view mirrors. For the back doors, I mounted the tweeter inside the midrange speakers. Speakers come with many to mount, so this was one of them.
I've decided against mounting the rear tweeters next to the handle, because speaker that is there is much larger and the space would be difficult, but not impossible to utilize for the new smaller tweeter. I didn't want to bother with that, because I never ride in the back seat anyway
. Speakers next to door handles were disconnected, could've easily left them connected, since I used factory wiring, but decided to leave them off so they wouldn't get in the way of tuned component speakers.
As you can see in the pictures, when mounting the speakers, I used gutted factory speakers as adaptors for the new ones, and it came out beautifully.
Oem speaker with all the excess removed and new mounting plate inserted:

After removing all unneeded plastic from the oem speakers, new speaker mounting plate just needed to be sanded on the outside diameter in order to fit inside the bracket, it's easier to see on the pictures
This way, they are installed very close to the original way. They don't need to be shaved in the back (as in Brad's install) in order to clear the windows because they're sitting so high off the door. I was able to use original rubber surrounds which direct sound output into the car instead of inside the door panel and keep road noise out. I was even able to use factory plug on the speakers and soldered wires from inside the the old speaker bracket from the new speakers( see the pictures).


I had to drill an additional hole in the bracket for tweeter wiring in the back doors, because original plug only has two pins. This was not excess for the front doors, because tweeter are mounted outside the speakers. I only have pictures of the rear speakers install, but the front doors are exactly the same except for outside tweeter mounting. Here is a picture of the finished rear door install.

The speakers were riveted back to the door using 3/16" medium length rivets.
I mounted the front tweeters using the same method of gutting the the stock tweeter and using it's bracket to hold the new tweets. Front and back speakers were exactly the same size and everything.
Crossovers were mounted without the enclosures they came in, because I didn't want to run into any clearance problems with the door panel.
I even found a present for myself
Techs left this cool LED flashlight under driver's seat carpet(you can only get under there after you remove side sill panels), when they replaced the carpet due to water leakage. This was because some drain tube got plugged by a leaf when the car was seating on the dealer's lot before sale.

Now for impressions
After adding the amp and sub, music was drastically improved. After I also swapped out the speakers, sound got more clear and bright. In short I'm very happy with the result, especially the difference that the sub makes
The amp has adjusments for front/rear gain levels, sub crossover level, and high-pass frequency. With the sub crossover set at 85hz(JL recommended) and sub output level turned up the car can really rumble. Bass and treble adjustments on the Nav are also functional.
Please let me know if you have any questions.
Modified by irom124 at 4:42 PM 11-25-2004