Instructions
Download the Halo Editing KIt installer on your hard drive and double-click on the file to launch the installation process. Follow the on-screen instructions to install the program on your computer.
Launch Guerilla, the tag editing application, by opening your Start Menu, selecting "All programs," clicking on "Halo Editing Kit" and selecting "Guerilla."
Click on "File," select "Open" and select the file that contains the tags for the character you want to edit. Typically, you can find character tag files in the following directory:
Modify character tags by changing the values of the various fields in the main window. Tags are grouped by categories. For example, all tags related to the weapons that a particular character can carry are located under the "Weapons" category. When you are done editing that particular character, click on "File" and select "Save" to save your new settings.
C:\Program Files\Microsoft Games\Halo: Combat Evolved\tags\characters