Ok I trying to install a bluetooth system and I need to know where the best place to tap into the speakers in my 06 civic with premium sound system.  I think I should tap in at the amp connector A (20p) shown here
http://www.8thcivic.com/forums/i-c-e-electrical-security-navigation/165790-complete-stereo-wire-diagrams-all-stereos-navigation.html
My bluetooth system has a mute button that give me 12v when the system is not active so what I'm think is I can Tap the speaker wires at the amp connector A(20P) and tap the Light Blue wire on audi unit B(20P) to the mute wire which would give the amp power when the bluetooth is not on .

Any help would be great.