You would not be able to find the first commit. The repositories for Fileutils, Shellutils, and Texutils do not exist, at least anywhere that I can find. They were merged as Coreutils in 2003 in a CVS repository. A few years later, it was migrated to git.

If anyone has original Fileutils, Shellutils, or Textutils archives (released before the ones currently on GNU's ftp server), I would be interested in looking at them. I looked into this recently for a commit [1].

[1] https://www.mail-archive.com/coreutils@gnu.org/msg12529.html