Basically it's appalling, the means of connection to that age of Henley is generally by a sweated ferrule, which can be seen in some of the photos. How the very small cable and the newer (??) grey PVC are actually connected is another question. There is a single bolt to secure the ferrule but it would certainly not be up to being used for a connection. (we now have some screw ferrules that fit these)
Question is, would the DNO upgrade this cutout FOC?
And for everyone else?
When the OP mentioned the locked box? Is he referring to the switch fuse or the light grey box? As the light grey box doesn't look locked to me