1954 Ferrari 375 Mille Miglia s/n 0456AM was originally shown at the
Paris Motor Show in October of 1954 wearing what appears in period
photographs to be light blue paint.  Immediately following the show's
closing, the car was purchased by Italian film director Roberto
Rossellini and photos of Rossellini with this car reveal that it was
still wearing this light blue color during his ownership.

While with current owner Wayne Golomb, the car has only appeared in a
shade of champagne-gold and Ferrari has even added this champagne
color to it's line-up of new cars and given it the name "Grigio
Ingrid."  (Rossellini purportedly bought 0456AM as an anniversary
present for his then-wife, actress Ingrid Bergman.)

My question, then, is this: At which point and in the hands of whom
did this Ferrari 375 MM s/n 0456AM obtain the golden paint scheme that
it now sports?

Have you seen this post?
http://www.italiaspeedforum.com/index.php?s=943552849bc03b658912d5b1c6ff5c4c&showtopic=206&pid=1972&st=0&#entry1972

Have you done a Google search using 1954 Ferrari 375 MM 0456AM.
Many hits. ...bill in corvallis

Thanks for the comment!

I have done much more than simply search available web sites.  I'm a
member of the Society of Automotive Historians as well as the Telaio
group of Ferrari historians and have exhausted resources with both
groups.  I have even snail-mailed my query to the current owner of the
car on more than one occasion but have never received a response.