I'm pretty well certain it was not serviced, but that doesn't mean it did not have a part number for control within Ford. Some parts were unlisted because they only came with an assembly...look up your main generator shell! There were many parts in Ford history that only came pressed or welded to something else, and I am sure there were numbers to control everything, probably even stuff like individual springs from the seat spring and the needle for the amneter, somewhere in the system.
With many unlisted parts you could make a flying guess from gaps in the catalog and probably find the archival drawings and change orders with some work, but it would be hard to guess even what group the patent plate might have lived in!