Thanks wazkelly.

I do already have the wiring diagram for the PBH4 and as you can see it doesn't match the pots that were supplied and pre-wired. I think they have supplied 2 tone pots and 2 volume pots, but the wiring diagram seems to be for 3 volume and 1 tone. I have now disconnected the humbucker wires and re-soldered the red & white back together but still not sure how to wire it given the pots supplied.