I believe that is for the armature, -and from what GMCTD told me a while back, the polarity shouldn't matter. There are only two wires landed back there under the rubber cap on some studs.
Those that are "in the know" regarding the DS-4 IP can tell you more than I can about the armature and what it does, I personally don't know for sure. I originally thought it sent IP shaft position to the ECM, but then learned that the optic sensor did that, -so I'm not 100% sure.