How do you add a4 pacific class add on to rail simulator?

To add the A4 Pacific Class add-on to Rail Simulator, first ensure you have the base game installed. Download the A4 Pacific Class add-on from a reputable source or the game's official store. After downloading, follow the installation instructions provided, which may involve extracting files into the game's directory or using a dedicated installer. Once installed, launch the game, and the A4 Pacific Class should be available for use in your scenariOS.