To find the cylinder number, you will need to consult a repair manual specific to your year and model Ford vehicle with the 3.4L SHO engine. The manual will have a diagram showing the engine layout and the numbering of the cylinders. The cylinder numbering usually starts at the front of the engine on one side of the "V" and continues sequentially.
You can often find these manuals online (some are free, while others are paid) or purchase one from a parts store. Alternatively, a detailed image search online (using terms like "Ford 3.4L SHO engine diagram" and your year) might reveal a diagram showing cylinder numbering. Remember to verify the diagram matches your specific engine model.