[John Webb]

The red tail (brake) lamp would only have been placed on the tender when the engine was running light. It should not be visible when the loco is hauling a train. The side it went on would probably have depended on which side of the loco the platform was at the time the lamp was put in place. There does not appear to be anything in the steam-age railway Rule Book or the Appendices which requires it to be in a particular position.

Regards,
John Webb

 

[John Webb]

Martin,
Glad to have been of help. Looking at my Hornby model of Mallard, there are two lamp 'irons' on the left hand side and one on the right of the corridor connection when looking at the back of the tender, just above the buffer beam. So I expect they'd hang a tail light on one or other of these.
Regards,
John