I think the London ones had the yellow and red buttons, rather than just the red ones. I have one from Grimsby Transport with motordrive, would love to get my hands on a london issue one though, not too many floating about.
Although this picture shows a standard electrically-driven OMO (and by the look of it, a non-LT) machine! The crew Almex Es might have been popular, but they didn't last for very long in London, possibly because the Gibson could better survive the bangs and whacks that portable machines could be subject to in service.
Oops!
Oops, you forgot something.