RE: Reflex XTR & JR 9303 - Cable?
Yes, it will.
No, there is no debate. As you can read on their homepage, the JR radios use a mono plug and only the graupner radios (made by jr) can't decide if they are mono or stereo.
The radio connector is pretty simple and you can read the wiring on the reflex homepage. It works without the resistor.