Here's the insulator and the bracket. The spindle is a standard straight piece that's designed to screw onto a crossarm. This is attached to a bracket that enables the spindle to fix to the side of the pole. A couple of screws is what was securing it to the pole.

The insulator is currently upside down in an acid bath. Despite several attempts to unscrew it with a strap it still refused to move.

The reason I've gone through so much trouble trying to remove this piece is because its my favourite type of cordeaux - the small single groover. These aren't that common and this is a nice stubby one as well..