In South Africa during the days of regular service many engines had assigned engineers(Drivers). They were allowed to decorate and paint the way they wanted. You could generally tell one of the locomotives by its appearance, versus a "Pool Power" engine. I do not recall any goofy colored jackets, except the RED DEVIL 3450(Comment--I hate that engine). They tended to put on some brass ornamentation, polished boiler bands, and maybe added a few touches here and there. But these engines were kept CLEAN generally. You would always see the driver, and or fireman wiping them down between runs. There was usually a little more brass inside the cab also. Sometimes a name plate would be on the front. These were usually wives, daughters or someone else special. There was a famous doctor who worked out of De Aar many years for the South African Railways. I believe there was an engine named for his wife, and daughters. We learned this through experience. My mother was in SA during 1976 and got very sick. They were in Port Elizabeth and she needed medical attention. This Doctor treated her, and after she was well they invited my parents to their home. He related the story about the engines named after his family. Those engines were running at the time(1976).
As for the Narrow Gauge or SG D&RGW I always considered them to be black boilers, except the 489 excursion. I could see them painting some 4-8-4's on the SG with green boilers. Those were the prestige engines the public saw more on passenger trains, so that would make some sense.
Just more useless commentary but am a bit tired of the Green Boiler stuff.
Greg