If that is a Ramco mirror, instructions on repairing/replacing it are here
. It is one of several Ramco support documents, available here
. I also recommend you call Ramco (if it's their mirror).
If it is a Velvac mirror, instructions for repairing may be available somewhere on this page
, or you may have to call Velvac for guidance.
Our 2008 HR Admiral has Ramco mirrors, but that may not be the case on your 2004.