He is referring to the Cadillac OEM mirrors that are installed at the factory on all passenger cars. I spoke to Richard today, and suggested that he look at the bottom inside of the mirror for a part number that is usually casted into the base. Then, I can look up the part to see exactly what Miller Meteor used, since they often used previous years parts in the production of the commercial chassis cars. Upon reassembly of my 1969 Miller Meteor, Ed found that the factory ground one side of the mirror base to allow for a change in the placement on the door. This is the type of change that makes it so difficult to find parts for our cars that fit correctly. Without knowing what year passenger car the part is used on, we have no idea what to look for when sourcing replacement parts.