Audio Systems: cdplayer into nissan maxium2002, lighting circuits, nissan maxima

Question
WOULD LIKE TO KNOW ANY INFORMATION ON HOW TO HOOK UP AN NISSAN MAXIUM 2002 W/UPGRADED BOSE SOUND SYSTEM IN IT.  I HAVE ALREADY HOOKED UP AN AMP TO THE STOOK SYSTEM BUT I KNOW SOMETHING IS NOT RIGHT!  THE MAIN PROBLEM I HAD WAS NO RCA OUT JACKS FROM THE BOSE HEAD UNIT. SO I JUST TAP IN TO THE SPEAKER WIRERS GOING TO THE STOOK BOSE SUB.  I KNOW THAT IS NOT RIGHT BECAUSE ITS JUST NOT SOUNDING RIGHT AND I LOST THE TWO REGULAR BREAK LIGHTS BUT THE MIDDLE ONE STILL WORKS.  SO MY IDEA IS TO PUT A NEW HEAD UNIT INTO THE CAR, SO THEN I WILL HAVE MY RCA OUT OF MY HEAD UNIT.  I HAVE AN 2005 JENSEN MODEL MP5720 HEAD UNIT TO PUT IN IT.WHAT DO YOU THINK?  ALSO IF I DO PUT THE NEW UNIT IN I'M GOING TO NEED THE WIRING HARRNESS FOR IT. CAN YOU SUGGEST A PLACE AROUND BENICIA, CA OR A GOOD WEB SITE.
                             THANKS,
                                   TIM

Answer
The people at www.crutchfield.com are the very best at this kind of thing.

There is some difficulty in interfacing with Bose equipment because they don't follow the same matching levels as other manufacturers.

Tapping into the speaker lines is not so bad if you do it right and if the audio is not too eqd for the speakers (such as Bose often does).  One problem with tapping is the voltage level is too high and overdrives the input of the amp being driven.  So, if you pad it down with a couple of resistors it lowers the input voltage and sounds better.  I have done this many times with good results.

Also, www.installdr.com will give you some wiring outlines.

I don't know if this model Maxima  combines data info on their speaker lines or not; some do and this can always be a problem with lighting circuits are combined (to save copper in the manufacturing costs of the car).

I checked crutchfield and they do have harnesses and adaptors for the Nissan Maxima, but I suggest you contact them on the 800 line for further advice.  For example, they have an adapter for adding an oem amplifier to the Bose headend, but you are putting in a new headend and wanting to adapt to the Bose power amps.  You might end up having to buy new power amps - which is not so bad a deal because they are not so expensive now days.  

Cleggsan