Well, I have my car back. Plan for this weekend is to take the Climate Control and Stereo front Panel Apart and see if I can change the colour. Interestingly enough, the ZC escapes here in Aus have Line In on the Panel, but it doesnt go anywhere.
I pulled the head unit out today, and the Line Ins are on the back of the deck : just two plain old RCA's.
The Stereo is made by Panasonic, and appears to be modular (Front panel, Rear Deck). My Deck is the 6 stack MP3 changer, and it also has CD Changer control (and then a set of CDC-In RCA's as well).
There are good options for expansion here!. Now to think about where to put the Aux in in the car.
Photos, as well as news how I go later on.
Of course, I have a backup plan. The Aus ZC (2006) escapes have silver trim, the Mazda Tributes Black (Piano - ergh). But the Escapes have Blue Back-Lighting (Ergh) while the tributes have Amber. If I cant make the escape Amber, Im going to bolt the tribute bits in instead using the escape trim panels.
I did have a really good look for the Aux power connector : on the BA/ZA/ZB escapes, there was an Aux power connector in the dash. Not on the ZC. The Aux power in the Boot is still there though.