Thunder1 is right: the official name of the color used for masts was "Spar Color." Now my senile memory is trying to figure out where I saw a reference to a color called "Mast." (Maybe it's the color of Cunard steamships' masts. Or maybe White Star. Dunno.)
Here's an interesting document from the Coast Guard Historian's webpage, detailing the regulations for painting CG vessels as of 1935: www.uscg.mil/.../USCG_Painting_Regs_1935.pdf . It does mention "spar color."
One curious point, though. In the text of the instructions the document refers to "spar color" as "No. 7." The CG Historian's Office appended a set of color chips from the same instructions, on the same date. On that chart, "No. 7" is a bright green - and there's no color labeled "Spar Color" (or "Mast"). There are, however, several shades of yellow ochre and buff.
I too wish the manufacturers would provide intelligent painting instructions for their ship kits, but that's probably too much to hope for. A couple of years back I sent Revell an e-mail about its latest re-release of the Taney. The advertising blurb in the online catalog said something to the effect that the ship "is now in service on the Atlantic Sea Frontier." That copy appeared on the web after the ship had been out of commission, and on public exhibition as a museum ship in Baltimore, for more than twenty years. I pointed out that Revell was missing an opportunity, in that connections with preserved ships help sell kits. I never got an answer, of course.
I figured out long ago that the people who write ads - and instructions - for several major model companies (mainly American ones) have no knowledge whatsoever of the subjects their products represent.
On the off-chance that anybody's interested, here are my contributions to the available material on the Taney and the Eastwind: http://www.uscg.mil/history/docs/plans/CGCRogerBTaneyColor.jpg and http://www.uscg.mil/history/docs/plans/CGCEastwind.jpg .
Don't trust the colors on the Taney drawing. I had to used colors that were available through Photoshop; then they had to be duplicated (we hope) with printer's ink - and gawd knows what may have happened to them when they got put on the Web.
Three cheers for anybody who builds a model of a Coast Guard vessel!
Youth, talent, hard work, and enthusiasm are no match for old age and treachery.