To find it:
1. Locate the main fuse and relay box: This is typically in the engine bay, often near the battery or on the bulkhead (firewall). It's a plastic box with numerous fuses and relays.
2. Consult your owner's manual: This is the best resource. The manual will have a diagram showing the fuse and relay box layout, clearly identifying the fuel pump relay. The diagram will typically use a symbol (often a gas pump icon) or label it clearly.
3. Look for online forums: Search online forums specific to Rover 75 owners. Many have threads discussing fuse and relay locations with pictures. Searching for "[Your Rover 75 Year/Engine] fuel pump relay location" will yield good results.
Without your owner's manual or a specific year/engine, pinpointing the exact location is impossible. Accessing the fuse and relay box usually involves removing a cover. Remember to disconnect the battery negative terminal before working with electrical components to prevent short circuits.