Example for mocking the instance method of a struct. I added the feature to Prig because I knew that Microsoft Fakes doesn't support [it](https://social.msdn.microsoft.com/Forums/en-US/3be5abc6-1b21-4322-a1f6-9573d38c4885/can-we-use-fakes-to-test-automationelement-methods?forum=vsunittest).

DateTimeHelper.cs

using System;

namespace StructInstanceMethodSample
{
    public class DateTimeHelper
    {
        public static DateTime ConvertServerTimeToTimeZoneTime(DateTime inputDateTime, string zoneId, bool __no_use__)
        {
            // dummy implementation
            var utcDateTime = inputDateTime.ToUniversalTime();
            return TimeZoneInfo.ConvertTimeFromUtc(utcDateTime, TimeZoneInfo.FindSystemTimeZoneById(zoneId));
        }
    }
}

DateTimeHelperTest.cs

using NUnit.Framework;
using StructInstanceMethodSample;
using System;
using System.Prig;
using Urasandesu.Prig.Framework;

namespace StructInstanceMethodSampleTest
{
    [TestFixture]
    public class DateTimeHelperTest
    {
        [Test]
        public void ConvertServerTimeToTimeZoneTimeTest()
        {
            using (new IndirectionsContext())
            {
                // Arrange
                PDateTime.ToUniversalTime().Body = (ref DateTime @this) => @this.AddHours(-10);
                PTimeZoneInfo.ConvertTimeFromUtcDateTimeTimeZoneInfo().Body = (dateTime, destinationTimeZone) => dateTime.AddHours(+8);
                
                // Act
                var inputDateTime = DateTime.Now;
                var timeZoneTime = DateTimeHelper.ConvertServerTimeToTimeZoneTime(inputDateTime, "China Standard Time", true);

                // Assert
                var diff = timeZoneTime - inputDateTime;
                Assert.AreEqual(-2, diff.Hours);
            }
        }
    }
}

mscorlib.v4.0.30319.v4.0.0.0.prig

<?xml version="1.0" encoding="utf-8"?>
<configuration>

  <configSections>
    <section name="prig" type="Urasandesu.Prig.Framework.PilotStubberConfiguration.PrigSection, Urasandesu.Prig.Framework" />
  </configSections>

  <prig>

    <stubs>
      <!-- 
          PDateTime.ToUniversalTime().Body = 
              (ref System.DateTime @this) => 
              {   
                  throw new NotImplementedException();
              };
      -->
      <add name="ToUniversalTime" alias="ToUniversalTime">
        <RuntimeMethodInfo xmlns:i="http://www.w3.org/2001/XMLSchema-instance" xmlns:x="http://www.w3.org/2001/XMLSchema" z:Id="1" z:FactoryType="MemberInfoSerializationHolder" z:Type="System.Reflection.MemberInfoSerializationHolder" z:Assembly="0" xmlns:z="http://schemas.microsoft.com/2003/10/Serialization/" xmlns="http://schemas.datacontract.org/2004/07/System.Reflection">
          <Name z:Id="2" z:Type="System.String" z:Assembly="0" xmlns="">ToUniversalTime</Name>
          <AssemblyName z:Id="3" z:Type="System.String" z:Assembly="0" xmlns="">mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</AssemblyName>
          <ClassName z:Id="4" z:Type="System.String" z:Assembly="0" xmlns="">System.DateTime</ClassName>
          <Signature z:Id="5" z:Type="System.String" z:Assembly="0" xmlns="">System.DateTime ToUniversalTime()</Signature>
          <Signature2 z:Id="6" z:Type="System.String" z:Assembly="0" xmlns="">System.DateTime ToUniversalTime()</Signature2>
          <MemberType z:Id="7" z:Type="System.Int32" z:Assembly="0" xmlns="">8</MemberType>
          <GenericArguments i:nil="true" xmlns="" />
        </RuntimeMethodInfo>
      </add>

      <!-- 
          PTimeZoneInfo.ConvertTimeFromUtcDateTimeTimeZoneInfo().Body = 
              (dateTime, destinationTimeZone) => 
              {   
                  throw new NotImplementedException();
              };
      -->
      <add name="ConvertTimeFromUtcDateTimeTimeZoneInfo" alias="ConvertTimeFromUtcDateTimeTimeZoneInfo">
        <RuntimeMethodInfo xmlns:i="http://www.w3.org/2001/XMLSchema-instance" xmlns:x="http://www.w3.org/2001/XMLSchema" z:Id="1" z:FactoryType="MemberInfoSerializationHolder" z:Type="System.Reflection.MemberInfoSerializationHolder" z:Assembly="0" xmlns:z="http://schemas.microsoft.com/2003/10/Serialization/" xmlns="http://schemas.datacontract.org/2004/07/System.Reflection">
          <Name z:Id="2" z:Type="System.String" z:Assembly="0" xmlns="">ConvertTimeFromUtc</Name>
          <AssemblyName z:Id="3" z:Type="System.String" z:Assembly="0" xmlns="">mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</AssemblyName>
          <ClassName z:Id="4" z:Type="System.String" z:Assembly="0" xmlns="">System.TimeZoneInfo</ClassName>
          <Signature z:Id="5" z:Type="System.String" z:Assembly="0" xmlns="">System.DateTime ConvertTimeFromUtc(System.DateTime, System.TimeZoneInfo)</Signature>
          <Signature2 z:Id="6" z:Type="System.String" z:Assembly="0" xmlns="">System.DateTime ConvertTimeFromUtc(System.DateTime, System.TimeZoneInfo)</Signature2>
          <MemberType z:Id="7" z:Type="System.Int32" z:Assembly="0" xmlns="">8</MemberType>
          <GenericArguments i:nil="true" xmlns="" />
        </RuntimeMethodInfo>
      </add>
    </stubs>

  </prig>

</configuration>

Complete solution is available in my google drive:
https://drive.google.com/file/d/0B4s_gXgDJAgbd21CRHpsVlFtNTA/view?usp=sharing