Green could be a modern thing. In childhood / adolescent hood, I was in signal boxes in Lisburn, Portadown, Kildare, Athy, Bagenalstown, Waterford (need a head for heights!), Kilmacthomas, Enniscorthy, Limerick Jct., Westport, Portrush, Ardee, Foynes, Moate.....etc etc.... and I don't recall ever seeing a green lever anywhere.....