Seeing the other build threads got me looking at this build again. So I already bought a preamp earlier as I had been planning on putting it into another build that never eventuated. I also have a few piezo rods and piezo discs. This should give me a few different options: single rod under saddle, two split piezo rods under saddle, disc under bridge and finally disc under cone. I also have an iRig Accoustic which doesn't work with my phone so I reckon I could pull that apart to get an apparently good mic and mount that somewhere.

In addition to the parts I already have I've now also ordered a few more things: a new cone, a couple of maple and ebony saddles, another spider bridge, and an ABR-1 style TOM bridge. I'm going to modify the second spider bridge and put the TOM on it. Then I can try out a few different designs and see which one I prefer.