Just did it. After wiring thru factory wiring harness and bypassing amp AND replacing all speakers, the factory system still had a couple of noise-reducers or bass-blockers in-line on the way back to the trunk, so I was forced to run 4 new speaker wires back to the trunk to connect with the post-amp wires. Not too difficult.
after the amp in the trunk they are direct wires (not bass-blocked) and you can splice the new wires to the factory wires in the trunk.
It's a pain in the ascot. Buy the crutchfield instruction kit for the seat and door removal instructions or email me for details. My friend bought the crutchfield directions and they are decent but not extraordinary. I'm just glad he did his milly the week before I did mine.
The harness in the trunk has both inputs and outputs for speakers. the OUTPUTS are: PINK/PURPLE: RF YEL/WHTwRED: Left Front and the outputs to the rear deck speakers should be obvious since they are right in front of your face. GRN/GRN,YEL and GRN,ORG/GRN,BLK are the rears and I can't remember which is left or right.

Crutchfield will list the millenia as 6x8 front and 6x9 in the back but the bose system is 6.5" in the front. 6x8 is for the P model.

Any other questions I'm sure I could answer them for you.

-Anthony

 

Update: On the output wires from the Bose Amp Harness: the pink is Right Front Neg and purple is Right Front Pos. The Yellow is Left Front Neg and Wht/Red is Left Front Pos. You screw that up, you're gonna be wondering why the sound is so mediocre coming from the doors.

These output wires going back up to the front are thicker (presumably because they are longer and run two speakers each from them (the tweeter and mid) in the doors. So do not mistake them for power wires.

 

How do you remove the back seat in a '01 Millenia S? I am stuck! Thanks!

 

Check drawingbelow. Rotate the release levers for the seat cushion to release per the highlighted box in lower right corner. Next lift the front of the seat cushion and it will roll right out.
The sear back is held in place by three bolts at lower edge. One in the lower center and one at each lower corner. Once these bolts are out then lift seat back straight up approx 3 inches to release the upper hooks and there you go.

[IMG]local://upfiles/1377/00B52FAE522243AF8A3797A17A2F1D68.gif[/IMG]

 

Found the wiring diagram. The post is somewhere on this forum. Just to let you all know. It's fairly simple but you have to run new wires back to the trunk from the head unit. No way around it unless you want your music to sound bland and pretty much horrible. I think there are bass blockers or some sort of grounds within the wires heading from the bose head unit to the trunk amp because it sounds bad. gotta bypass those. I did and they sound great now.

 

I cotacted Crutchfield and they told me they have a head unit adapter for my 2000 S (#120707901)! So am I still gonna have to rewire all the speakers, including the front,to bypass all the bass blockers? By the way my front speakers are only 4"! What kind of speakers are you using?

 

I have a 2000 S just installed a new Clarion it was fairly easy. only hard part was someone had the car befor me and gutted the center where the head unit goes so i had to make brackets and a new plate for the front. i just fiberglasses it, i did have to run wires to the trunk for the fronts and rears but its easy. run them in the wireing harness on the driver side floor board. the pink and purple is Right Front yellow and blue is Left Front from the yellow bose amp clip. also in this post it says red/white BECAREFULL red/white on the 2000 is amp power. i am useing the bose in the doors still and the bose in the rear. sounds great. in this post also are the wireing scamatics for the power ground and memory their all on 1 clip. i just cut them and heat shrink and soldered them. but it is fairly easy. done with the whole install in less than an hr after the fiberglassing and dry time. if it was just to pull the bose and install then a little less than an hr.

 

Ground wire is Black w/ Red stripe
Battery 12v all the time is Blue w/ Red stripe
Switched voltage wire (only has power with key in ACC or RUN is Pink w/ Green stripe.
this is correct, found this in a post by Babyhuey so he gets all the credit.