interior lighting and aesthetics

I own an 07 impala lt. The interior lighting on the dash and guage cluster is an ugly bluish green color, and I want to change the backlight source to a pure white. I would eventually want to change the needles on the cluster to either a pure white, or a chrome needle with a white backlight (as featured on the new lincoln mkx). Once I get these done, the digital radio and cluster information screen will still be the same ugly blue color.. I was wondering if they could be changed as well with a simple tune. (they might use the same screen for multiple models.. meaning multiple color options)

How would I go about doing this? I'm afraid that I would have to rip out the entire dash to find the lightsource, which leads me to the next question.. are they LED lit or are they lit by fiber optics?

I'm so lost as what to do :[