Ok I will have a look at the other Boyer post and try and pick out the best option, my plan was to machine the shaft, bearing housing, rotator and make up a new smaller plate for the hall effect switches, why because I can.
That is basically what SRM are doing.
Going by the instruction manual you buy the kit and fit it yourself there is no machining of the original housing, so it can be rebuilt at a later date if so needed.
My biggest concern is the heat, with the hall effect sensors being inside the magneto, not much cooling going on in there!
Burgs