The following book might be helpful to some.

The Complete Carriage & Wagon Painter by Fritz Schreiber, New York,
1891.

There is a lot of information about striping, lettering, and the use of
"gold" paint (it's bronze) and of gold leaf.

The two copies I have are reprints, published by Windy Row Reprints of
Peterborough, New Hampshire in 1973 and 1974.  I do not know if the
book is still in print.