I removed the stock 3.8.0-19-generic kernel (and meta packages for the stock ubuntu kernel) and installed the 3.9 mainline kernel, do I need these 2 packages or can I remove them?

~$ apt-cache policy linux-libc-dev

linux-libc-dev:

  Installed: 3.8.0-19.29

  Candidate: 3.8.0-19.30

  Version table:

     3.8.0-19.30 0

        500 http://us.archive.ubuntu.com/ubuntu/ raring-updates/main amd64 Packages

        500 http://security.ubuntu.com/ubuntu/ raring-security/main amd64 Packages

 *** 3.8.0-19.29 0

        500 http://us.archive.ubuntu.com/ubuntu/ raring/main amd64 Packages

        100 /var/lib/dpkg/status

~$ apt-cache policy libc6-dev

libc6-dev:

  Installed: 2.17-0ubuntu5

  Candidate: 2.17-0ubuntu5

  Version table:

 *** 2.17-0ubuntu5 0

        500 http://us.archive.ubuntu.com/ubuntu/ raring/main amd64 Packages

        100 /var/lib/dpkg/status