Where does the oil pressure switch go on a buick v6 3.8?

The location of the oil pressure switch on a Buick 3.8L V6 engine varies slightly depending on the year and specific engine configuration. However, it's generally found on the engine block, near the oil filter.

It's usually a small switch with one or two wires attached, and often easily accessible. You'll likely need to consult a repair manual specific to your Buick's year and model to pinpoint the exact location on your engine. A picture of your engine would also be helpful for a precise answer. A Chilton's or Haynes repair manual for your specific vehicle will have diagrams and clear instructions.