Hey Andy, thanks for your input!


I might plump for:

4) Two separate unfused spurs in 2.5 mm^2 taken from the existing socket
(with the cable for the furthest socket run through the middle mounting
box, but not connected to anything therein).


I like it - still not stricltly 'cosher' because there's two spurs
effectively from the same original DSO, but at least the cable is protected
to being used within its load limit.


Nice one!

Now to struggle with four lots of 2.5mm sq. conductors in the one socket.
Deep joy (in a deep box!!!)

Cheers

Al.