If it were my problem, I'd drill it off (the rivets are soft, and it's easy), strip it, make sure the serial number matched my title, fill the rivet holes with JB Weld, re-finish and paint, then re-adhere with outdoor bonding tape.
Originally, the ID Plate is fastened on from from behind the outer skin, before the inner skin goes on.Your plate should not have any rivets in it. It has been removed and improperly re-mounted.
There's some variation, but generally, The letter/number on your plate should start with an I for International, then a 22 for the length, then 8 for year, there might be a T for twin, an S or J for location of manufacture, and then the last numbers tell its place in production. Sometimes instead of a T for twin, or a D for double, the twins are below 500 in production number, and the doubles start after 500.
Pardon my patina, but the image shows how it should appear in its original fashion. If you can read it, My Land Yacht trimmed (non-International trim is designated by letter O) 20 foot 1968
Double (Series starts with number 500) was the 37th built in Jackson Center