How do you connect twin hooter with relay please explain connecting the different points on the relay... The vehicle currently has a single hooter with a single connection plus Earth?

To connect a twin hooter with a relay, first ensure the vehicle's electrical system is off. Connect the positive terminal of the battery to one terminal of the relay (usually the 30 terminal). Connect the other terminal of the relay (terminal 87) to the positive terminal of the twin hooters. Then, connect the hooters' negative terminals to the vehicle's ground (Earth). Finally, use the existing single hooter's connection to trigger the relay by connecting it to terminal 86, and ground the relay's terminal 85.