Regarding replacing the black on a nameplate.  I am not for sure,
but I believe that most original nameplates were printed with a black ink.
Wear and tear with the passage of time wears away the black as well as
the raised portion of the nameplate, such as the Tempo plate.

I polish the plates and then spray a light coat of black lacquer paint on
them if they were black to begin with.  I have seen some original Seeburg
plates with a blue color on them.  After the paint dries I carefully
remove the paint from the raised portion of the name plate with an X-acto
knife or razor blade.  I then lightly use 0000 steel wool to polish the
raised portion of the name plate.  Sometimes I have to paint & polish
several times before I get the results I am after.

Don Teach