bypass bose but still want onstar

i have a 07 trailblazer and hate the whole bose system.i wanna change the headunit,front and rear speakers and put in different amps.so my questions are 1)what size speakers are in the doors(i know the bose speakers are weird sizes)and 2)i still wanna use the onstar and chimes.i know the chimes and onstar work thru the front door speakers(or thats what ive been told).so,if i scrap the whole system,how do i still use onstar and have chimes?thanks for the help

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9

hi,

did work on a friend's SS a few months back...i'll see what i can remember.

1. the front doors have a 7 inch or so driver in them, you can make an adapter plate out of mdf and put a 6.5" in there.  3"? in dash---make plate for tweeter.

2. the rear doors have a 5.25" driver, unless using another speaker of the same size, you'll need to make an adapter plate/ring.

3. you can use a Metra GMOS-01 for the chime/onstar interface.  you'll need to add a speaker to the left front output of said unit.  can't remember if the bose system in the Trailblazer has rear fill or not.  you might be able to use those.  the interface will also provide switched accessory as well as navigation related wires (if needed).

hope this helps

mark

if it chimes out of the dash speaker then yes you can go that route.  the interface will turn the bose amp on for chimes and onstar.

m