Remove the previously installed locking core and set from your file cabinet by unscrewing the retention bolt located through the locking core on the inside the file cabinet and tapping the locking core out of the hole from the inside of the file cabinet. You may leave the locking arm running through the side of the cabinet.
Press the locking core into the lock hole at the top of the file cabinet.
Screw the retention screw into the lock core with a screwdriver. This will be located on the inside of the file cabinet. The screw is tight enough when the lock core is flush with the outside of the file cabinet.
Place the square end tab on the locking arm into the hole on the lock core to properly align the locking arm with the lock core.
Secure it in place using a screw and screwdriver.