Hi Sidewinder and
to the forum.
To convert the Magic Pie from an internal to external controller is not a particularly straightforward job to do, but if you have reasonable soldering skills, and can cope with some minor dismantling and major re-wiring, then it can be done.
The internal controller, along with the existing wiring harness that passes through the axle, needs to be removed so that new wires can be run through the axle. All of the external connectons; Brakes, Throttle, Pedelec, Cruise Button and Battery Cable etc. will probably need to have their connectors changed to suit the new external controller.
Check out
this post for more details and a few pictures too.
Alan