I have an 07 coupe without the dual climate faceplate, but found someone who is willing to sell me an 06 coupe faceplate with dual climate control for $60. Is it just plug and play or will I have to tweak it for it to work?

 

Yes, it'll work.

However, the power circuits are typically to blame for a lot of the failures of these radios, so if your headunit fried your faceplate and controls, it'll do the same to the new one.

 

I read somewhere that I'll have to desolder and resolder some chip, right? Is it really just plug and play?

 

Having the button there won't hurt anything, it just won't be functional.