On Boracay the throttle pod is made by Lewmar
(When I looked they seemed to be the only makers.).
We have a flat plate that the compass and the guards fit through.
These are screws in the flat plate that hold the throttle pod in position.
Removing those screws allows the pod to be moved slightly, just enough to access the rest of the mounting screws.
Once half of the throttle pod has been removed the internal workings of the throttle pod can be accessed.
It is then not difficult to change the direction of the throttle/gearbox movement.
The main thing to watch out for is not to loose any of the many unique tiny parts
that are only replaceable by buying
a complete new assembly.
If this is you and you need more info let me know and I will get some photos etc.