Use a text editor such as notepad to edit the "UTCustomChar.ini" file in the "/My Games/Unreal Tournament 3/UTGame/Config/" directory. Locate the line for "Johnson" and overwrite it with the following line:
Characters=(CharName="Johnson",Description="An ex-military soldier jumped into the Tournaments after shell-shock and repressed trauma took too heavy a toll on his mind. He is competent, but volitile.",CharID="F",bLocked="false",Faction="Ironguard", PreviewImageMarkup= "",CharData=(FamilyID="IRNM",HeadID="D",TorsoID="B",ShoPadID="B", bHasLeftShoPad=true,bHasRightShoPad=true,ArmsID="A",ThighsID="B",BootsID="B"))