I know very little about the Southern, but danged if it doesn't look like a white stripe in those photos that were posted, and not a reflection. Course one has to wonder about painting anything on the pilot white, since it won't stay that way for long.
The bottom of the pilots were painted white from time to time on many of these engines, including the 1401, but they were not painted white all the time. I think that's been made clear by commentary above, discussing the preferences of the various shops. There are photos showing a given engine with the stripe, and other photos of the same engine showing no stripe. In some of the pictures it is indeed a reflection, and reflections make other parts of the engine look white as well that were clearly not parts that were painted. Here are several more shots of the 1401, both showing the engine with clearly no white stripe on the pilot. One is from 1933, and one is from 1953.
Southern Steam #1401
Location: Charlotte, VA
Date: July 1933
Type: 4-6-2
Photographer: Unknown, photo marked "from the Collection of Harold K. Vollrath"
Southern Steam #1401
Location: Alexandria, VA
Date: July 1953
Type: 4-6-2
Photographer: Unknown, photo marked "from the Collection of Harold K. Vollrath"
