This may well be how it comes pre-wired from the factory, but it's obviously wrong. Can someone check how a standard JM-1 kit plate is wired, and if it is done as shown on the diagram, can the diagram be modified to state that the tone pot wiring needs to be modified so that on each one, the capacitor leg to the pot tag needs to be swapped to the opposite end as I've shown below?
Obviously if the factory do wire it like this, then getting it corrected there would be a jolly good thing. If it's just the wiring diagram that's wrong, then getting that amended would be good.