- Make sure that the roof box is locked
- Using the original key turn the key 45 degrees CLOCKWISE "so the big hand is at about 10:30” and withdraw the key.
- Push the master key (the one with the square cornered head) into the lock barrel. When you withdraw it the lock barrel will come out.
- Put one of the new "one key locking systems" onto the master key and insert it into the lock opening.
- Put your thumb over the barrel and withdraw the key.