Got a new temperature sensor for the thermostat housing and I'm not sure which wire is the positive or negative, PO had direct spliced the wires to the old sensor. Any ideas? I have the 12 volt and the ground coming from the engine side I just need to know where to connect them on the sensor if it even matters. Connector on the sensor has terminals labeled "A" and "B", B side is slotted.

You can wire it either way. There is no polarity on the sensor.