The Southern performed many improvements / modifications to their steam fleet during the late 30s / early 40s. The SRHA TIES magazine ran several articles on differences between shops (mainly on Ps-4s) several years ago, and I think these are still available. The color postcard view of 1452 was taken in Asheville (I think) and the work would have been done in Spencer. The high valve ladder steps to the running boards are a dead giveaway to Spencer. The same modifications are evident on several different classes of steam locomotives.
The Southern was one of the best in terms of keeping their steam locomotive fleet in good working order and performing many of the modifications / upgrades in house.
As for repainting green, that would have been done post 1927. Any TS or Ts-1 in passenger service during the 1920s would be in the black scheme with pin stripes for decoration.
Attached are some early images of 4-8-2 locomotives I found on southern.railfan.net. Most of these are in the 1917 - 1920 time frame. 
