Were you looking to replace your 2011 GMC 2500? Here is a thread when I bought mine, but a little different circumstance.Thread about buying a used 6.0
I dislike Ipod and itunes. But, my daughter now has an ipod. Here is what I do, but I am SURE there is a better way. Itunes will see any MP3 or music file you have on your computer. We buy all of our music from Amazon and keep it on their "cloud"...