How do I change Unity top panel Icons?

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http://askubuntu.com – I am using Faenza icon theme and it looks great , but I dont like its top panel icons. I would like to continue to use Faenza but replace the top panel icons with ubuntu-mono-dark. How can I do that?(I suppose that I have to transfer some files from mono-dark to faenza , but I have no idea which). Thank you in advance. (HowTos)