Is there a retainer clip or any such device to hold the reservoir on an '81 GL500 SilverWing front brake master cylinder? I assume the "O" ring is the only seal, too? After removing the two screws, it will turn around about a quarter turn. I thought I saw someone pry it off of another one once, but would like to be sure it isn't being held by a clip or something. It is the original rectangular reservoir and mc with an offset perch. Thanks in advance for any answer forthcoming.