Since there is obviously a backstory for everything in Star Wars, here is a very special question that has been on my mind for a while now.
At the beginning of his "life" C-3PO is "naked", his outer shell is added a little later. But these parts are old and dirty.
Later in his "life" C-3PO has a golden shell. Does his golden shell consist of his original parts that were painted golden or cleaned or are they completely different parts? Is there a story about that?
Is there a story about his silver leg?
I know there is a comic that explains his red arm from Episode VII.