Fresh Install of OSX Mavericks on new 15" Macbook Pro retina

I have a brand new 15" Macbook Pro and would like to do a fresh install of OsX Mavericks,

the app store is telling me I can't download it, "OSX mavericks can't be installed on this computer" it already has mavericks, but I want to install a fresh copy, how do I do this?

Thanks,

Bryan