EE WAS ASSISTING MECHANIC WITH INSTALLING A HITCH PIN. THE EE PICKED UP A HITCH FROM THE STORAGE AREA AND PLEASED IT ON A TRUCK FOR TRANSPORT. WHILE PLACING THE HITCH ON THE TRUCK THE EMPLOYEE 'S FINGER WAS CAUGHT BETWEEN THE HITCH PIN AND TAILGATE SUPPORT. THIS CAUSED A LACERATION OF THE LEFT INDEX FINGER.