How do i change my iDevice iTunes library persistent ID?

I had my iPad synced to my computer, and my hard drive crashed, after a reïnstall of Windows, iTunes generated a new library persistent ID for me and i won't be able to sync my iPad to my computer. The easiest way would be to change the computer iTunes library persistent ID to the iTunes library persistent ID that's on my iPad, the problem with that is that i already have synced my iPhone to my computer and i would lose the stuff on my iPhone. Can i change the library persistent ID on my iPad? I have full root access on my iPad, but i don't know where it's stored and how to change it.