Hi! At one time I was employed by SEEB 33Kv construction department, about the time of your photo, together with Wingham Engineering, were engaged in maintenance and repair of a tower line in that area. I think the colour you are looking for is Brunswick green, least ways that was the colour name on the tin the chaps used to touch up the cranes and dumper on site. Funny how after all this time it sticks in my mind, especially now, sometimes I have problems remembering what I did yesterday.