Got started, but need some help

[gtasound]

Car - 02 Lincoln LS (will take pictures and upload on monday)

Head unit is the Pioneer avh 7" dvd player - only got it cause it has +4 v triple pre outs for the SPL I want.

There's 8 stock speakers in the car that I'm hoping will do the trick for now.

2 6x8 in the front door

2 6x8 in the rear door

2 3.5" center stage in the console

2 6x8 in the rear deck (powered by seperate stock amp doing only bass)

All speakers are stock Alpine. They sound good so I'm hoping I could use them.

I ran all wires necessary to the trunk (3 sets of rca's and 4 sets of speaker wire). 1/0 from battery to a fuse block that has two 4ga outs. I tied the center stage speaker into my fronts to use them as the mid-highs. I have a PowerBass 700.5 amp running the doors right now, but I'm not to happy with the output, or the tuning.

What I want to do is build a SPL sedan.

My originial plan was to do the high end first because bass can easily be added. Well right now I just have a generic box with two 12's for temporary pleasure.

I was thinking because my car already has alot of speaker in it, I could build a 5-way system to get my mids extremley loud and smooth as well as my highs to be ear peircing but with no shrills or harshness. So what I hoped would work was the following

- Add tweeters in each door for a total of 4 for my highs

- Use the center stage speakers for my mid-highs

- Use the 4 door speakers to do only my mids

- By-pass the stock amp and use the rear deck speakers for my mid-bass

- Custom build 3 12" subs into the truck (Can't fit 15" in there) for my sub

Now the way I have it setup right now, it gets really loud that I can't hear my self talk (and just barley here myself shout), but the problem is, I can't hear it too well outside the car with the doors closed the the windows down (even standing next to it). But that's what I want, for it to be heard outside the car.

Oh before, I forget, I'm trying to keep AS MUCH if not the whole build (aside from the tweeters in the door and the subs in the trunk) as stock and stealth looking as possible to keep the interiors eligence.

I'd like some help knowing what to do from here cause I don't want to start experimenting to find out what works only to find out it doesn't work or sound good and have spent a ton of money. That's another thing, money's not tight, but it's not at an abundance either, but this project has started already and I intened on finishing it... soon.

Please help. If you agree that I should work with the stock speakers, what frequancies should I cross each component at?