I might have that impedance thing wrong. All I know is that when I started my google research I came across "blending" Piezos with Magnetics could be a bit of a problem. I saw several builds and some top end guitars like PRS that had extra circuitry to blend the pickups. So I shied away from that quick smart and decided to just try and make it work with a piezo.
The build is on hold just now as I used my last waterslide decal on it and it did not take and has lifted. So until I get that done I can't apply any more naughty oil. I don't have access to a laser printer so I am waiting for a good time to hit up my bro-in-law for a favour.