I've buggered about with pickups and positioning for the best part of a year now, and have finally settled (for now) on a Jazz configuration with a MM hum bucker next to the bridge pup. I don't use it much, but blending it with either of the other two (all 3 at once isn't anywhere near as impressive as I thought it would be) adds a lot more definition, particularly when I'm just using the neck pup for a 'P' bass sound.
I've put mine touching the bridge pup, as I thought that's where I thought it sounded the best with my setup, but the OP's looks equidistant between the J pups.