Texas & Pacific Building Painting Standards
From Jim Ogden:
 My TP experiences are from Louisiana where a number of frame depots are off line but still exist.   I think the key to understanding the colors is to see who the president was.  Prior to 1917 the TP was under the thumb of George Gould and I think the original colors (as found on the refurbished Smithville, Texas depot which has been moved to north of Henderson, Texas) were  chrome yellow and bronze green, or at least I was told this was the bottom-most color  they could find and they matched it with latex. 
Lancaster took over as president in 1917 and I think he began using something close to buff or a yellow ochre paint with brunswick green trim paint (basically a black using a copper salt).  If you have Steve Goen's color book, you can see Tom has some photos of structures in Lancaster yard (FW) with the buff paint and there is also a photo of Roscoe, Texas with a buff paint scheme.  The trim even looks an off-black.
When built, the depot in Mineola had orange brick and I was shown an unscorched one by the city manager and it is close a swamp holly orange.    After the depot burned, I was  told the TP merely rebricked the outside of this structure with beige brick and put a flat roof on it (which always leaked).
Mr. Vollmer took over in 1943, and by the end of steam they were actively refurbishing depots after their successful modernizations of Grand Saline and Sherman, Texas, and started using white as a secondary color since it matched the gray asbestos shingles better and was already in use on brick depots.    I think everything then started getting white paint about this time although the long repair shed in Texarkana seems to have kept its yellow buff color until it burned.  From what I undestand
AFAIK, the red brick depots in Gretna and Bunkie always had white trim although I found extremely dark Brunswick green trim paint inside the doors and window muntins in Bunkie when I walked through just before UP gave it to the city.  But all the exterior concrete was white-- ditto for Gretna.  The Alexandria depot was more of a MoPac design and had colonial yellow trim with brown accents.  The red brick  Plaquemines depot  resembles Wills Point and I think it always had white accents as well.
From Tom Stamey
All the wood framed depots of the T&P that I saw such as Strawn, Denton, Hooks, Sherman, Stanton, Toyah, Merkel, Santo, were all painted white.  Most roofs were red rigid asbestos which was subject to change due to hail storms when asbestos fell out of favor.  In Texas, a high percentage of the stations were red brick with white trim on doors and windows..  There were some exceptions to that like Weatherford and Midland, Tx that had tan brick.
The Mineola station appears to be a different matter altogether as I heard (but can not testify to it) that the station at one time was Swamp Holly orange and black trim.  I have no information on how long it might have lasted or if indeed that is correct.  A lot of T&P section houses were orange and black in the 1920's,30's and into the 1940's and I have always wondered if some were mistaking that for the depot color.  Even those began being painted white.