I just opened up the bass to install a series/parallel switch. The series connection sounded so much better that I decided to just connect it series all the time. Huge improvement. Now it has more of that stringray grunt.
If you are interested in doing the same, the parallel connection is black/red connected to the white wire going into the preamp and green/white connected to black (as well of the shield of the pickup cable).
To connect it series, connect green and black together and insulate. White connector to black from the preamp. Red connects to white from the preamp. The shield is not needed and cutting it off shouldn't matter.
If you are interested in doing the same, the parallel connection is black/red connected to the white wire going into the preamp and green/white connected to black (as well of the shield of the pickup cable).
To connect it series, connect green and black together and insulate. White connector to black from the preamp. Red connects to white from the preamp. The shield is not needed and cutting it off shouldn't matter.