AC Delco P420 is what the parts store gave for the replacement pigtail. But it doesn't fit the sensor due to the plastic guide between two of the pins. All three wires are solid gray. Also the retaining clip isn't compatible with the one on the sensor (won't hold it on).
The parts store confirmed the sensor shows a little tab between two of the pins.
The parts store is calling AC Delco tomorrow to see if the part was mispackaged or miscataloged.
Glad I checked this before chopping off the old pigtail.
I noticed that the little purple rubber gasket falls off the old pigtail pretty easily too so maybe that contributed to the bad connection. The old sensor pins look clean and shiny though. I think the problem is where the wires contact the pins on the pigtail.
Hope ya'll don't mind me replying to myself, but figured this info will save a few of you some time. Maybe someone will have a better or easier way to remedy this issue.
I've attached a photo of the old sensor and apparently wrong pigtail.