Colour light signals

[bécasse]

You need to look for contemporary photos of the Kent electrification schemes which included a lot of new c/l signalling. The work was done in two distinct stages, 1958-59 for the Chatham routes and 1961-62 for the Tonbridge ones, and the styles evolved more than one might think between the two even though both looked to be typical Southern Region schemes (with three-light feathers, for example).

 

Without looking through photos, and thus relying on an ageing memory, I suspect that the signal formation you are looking for was, at best, unusual and may well have been non-existent. My memory suggests that the platform signal was placed on the gantry post at a lower level and only the "fast line" signal was mounted out on the gantry (have a look for photos of Tonbridge, although quite a few SE stations had fast lines for boat train traffic). There was logic to this arrangement because it made it much easier for a guard to see the signal before giving the right-away.