Hello,
Brandnew to forums (after many years in IT, oh well) so hopefully I'm doing this right. I've spent many hours trying to Google the answer with no luck. I believe something chewed through the wires on the harness
connector to the upstream O2 sensor and I can't tell which wire went where on the pigtail. If anyone can assist, that would be greatly appreciated. Let me know if more info is needed and many thanks for taking a look.

 

Just noticed I forgot to add a somewhat significant piece of information - it's a 2006 Mazda 3 with the 2.3L engine.