Looking the goods Brendan
You could also make that box a universal power supply, EG: 8.1V, 12V and 5V (usb hub).
I did all this in a plastic box and it is fitted to the scope so i can feed the camera, usb hub and everything 12V like mount, heaters etc.
This means that i have only two wires going to the scope that i don't even have to separate, usb and 12V DC.
The box with electronics is very light and this way the bulk of wires can be short and it all turns with the scope (so no wires get stuck).
If you have an old worn out battery then you can use that as an adapter, take batteries etc out and wire the + and -, then glue it back together.
Martin.