Not sure if anyone has done this yet but decided I might as well write up a tutorial upon completion of mine
Tools needed:
1x small phillips head screwdriver
1x small flat head screwdriver
Linear polariser film (preferably with adhesive side, I got mine from http://www.3dlens.com/shop/lcdpolarizer.php)
Acetone
Scalpel/Razor
Procedure:
1. Remove climate control from car.
2. Remove the temperature knob along with the nut behind it
3. Remove the 4 screws holding the front half of the unit to the back half
4. Using the flat head undo the 4 clips, and the front part should pop off
5. Undo the the 2 screws holding the back circuit boar, then push on the part where the plug goes to slide it out
6. Undo the 4 screws holding the front circuit board to the face
7. You should be able to pop the circuit board out now
8. Now comes the tricky part, using a scalpel slowly try and peel back the existing polarising film. Easiest to work from the corner and slowly sliding the scalpel along the glass
9. If there's adhesive residue left over on the screen, then use acetone to remove it
10. Time to apply the polarising film, if you place it the correct way it should look normal (white backlight with black writing), but if you turn it 90 degress, it'll reverse the colours
11. Once your happy with it, cut the film to size and apply to the LCD screen
12. Reassemble the climate control unit and reinstall into car, now you should have something that looks like this