I also have been doing thorough investigation on this...
it is very dificult to separate the climate control and audio control, they sahre the same circuit board.
I gave up in going this direction months ago.
Now, i am investigating alternatives method to mount lcds, my projest is to have a car computer displayed on touchscreen lcd.
The car pc runs windows/linux, have yellow page info in it, unlimited mp3s, can be used to play movies...etc
Chronicle: >>2003 SL Super Black AWD Murano / Navteq Intelinav Software/ Pro-kit Mount & Holux GPS Receiver / Magnet Bra / Autopark Sensor/ XM Roady SAT Radio / OEM HID bixenon headlight retrofit / Trim-
Gard Chrome Body Side Molding / Nissan Murano Decals/PAC adapter/ Cargo Net
-- SOLD on 07/20/2006. Thank you everyone!