I think you are confusing markers and class lights. A green class light (or flag) on the engine of a scheduled train indicated following sections. The last section had no class lights or flags. Extra trains displayed white class lights or flags. Red marked the end of the train, and if the train was in a siding and clear of the main track the marker would be turned to either green or yellow (depending on the railroad) to indicated it was in the clear and safe to pass.
JBWX
Edited 3 time(s). Last edit at 01/24/2020 11:06PM by John West.