using System;

using System.Xml;

public class Program

{

    public static void Main()

    {

        XmlDocument xmlDoc = new XmlDocument();

        xmlDoc.LoadXml(@"<NonFuel><Desc>Non-Fuel</Desc><Description></Description><Quantity/><Amount/><Additional/><Dispute>0</Dispute></NonFuel>");

​

        XmlNode nonFuel = xmlDoc.SelectSingleNode("//NonFuel");

        XmlNode dispute = xmlDoc.SelectSingleNode("//Dispute");

​

​

        XmlNode xmlRecordNo=  xmlDoc.CreateNode(XmlNodeType.Element, "Records", null);

        xmlRecordNo.InnerText = Guid.NewGuid().ToString();

        nonFuel.InsertAfter(xmlRecordNo, dispute);

        Console.WriteLine(xmlDoc.InnerXml);

    }

}