It would appear that the pups need to be much closer to the strings than I have previously experienced ( 2.8mm is the PBass standard apparently )
The Sth pole of the HB is still not playing fair so a bit more investigation is required, I'm seeing the correct impedance and also seeing it change as expected through it's vol pot so somethings not quite right but it's now getting closer to the stage where I start setting the neck and bridge properly