Loading a specific DLL in PowerShell

I'm attempting to load a specific DLL within PowerShell using the below code:

function New-SpecificAssembly {
    [CmdletBinding()]
    param (
        [Parameter(Mandatory = $true)]
        [string]$Path
    )
    process {
        [string]$Fullname = ([System.Reflection.AssemblyName]::GetAssemblyName($Path)).FullName
        Write-Verbose "Loading: $Fullname"
        Write-Output ([System.Reflection.Assembly]::Load($FullName))
    }
}

$d11_Security = New-SpecificAssembly -Path 'C:\Windows\Microsoft.NET\Framework\v1.1.4322\System.Security.dll' -Verbose
$d11_Security | ft ImageRuntimeVersion, Location -autosize

However, I cannot find a way to get it to load the .net1.1 version of the DLL. The above returns: v2.0.50727 / C:\Windows\assembly\GAC_MSIL\System.Security\2.0.0.0__b03f5f7f11d50a3a\System.Security.dll.

Additional Info

LoadFrom

NB: I've also tried using LoadFrom as detailed here: https://stackoverflow.com/a/9447959/361842; however that returned the v2 version of the dll. Checking https://msdn.microsoft.com/en-us/library/1009fa28(v=vs.110).aspx

The LoadFrom method has the following disadvantages. Consider using Load instead.

If an assembly with the same identity is already loaded, LoadFrom returns the loaded assembly even if a different path was specified.

That said, it turns out that Load has the same caveat despite the recommendation. i.e. per https://msdn.microsoft.com/en-us/library/ky3942xh(v=vs.110).aspx:

FileLoadException is thrown if assemblyString specifies the full assembly name, and the first assembly that matches the simple name has a different version, culture, or public key token. The loader does not continue probing for other assemblies that match the simple name.

LoadFile

I'd thought LoadFile may work where LoadFrom failed, given we're explicitly stating the file path. https://msdn.microsoft.com/en-us/library/b61s44e8(v=vs.110).aspx. Sadly though the documentation doesn't report any potential issues here (beyond dependencies not being loaded), however this still returns the wrong version:

ImageRuntimeVersion Location
------------------- --------
v2.0.50727          C:\Windows\assembly\GAC_MSIL\System.Security\2.0.0.0__b03f5f7f11d50a3a\System.Security.dll

More Detail

NB: Since we're looking at an x86 dll, I'm running PowerShell x86 (i.e. %SystemRoot%\syswow64\WindowsPowerShell\v1.0\powershell.exe).

The reason for this is to aid in investigating an issue migrating a legacy site from an old Windows 2003 server to Windows 2008 R2, having already followed the steps outlined here: https://docs.microsoft.com/en-us/iis/install/installing-iis-7/how-to-install-aspnet-11-with-iis-on-vista-and-windows-2008. Sadly we don't have access to the source for this site, so recoding is not an option. The error mentions InvokeMember("_GetRoles", /* ... */, so I assume they've used the reflection technique for enumarting roles as outlined here: https://www.thecodingforums.com/threads/enumerate-roles-a-user-belongs-to-seek-vb-net-sample.85831/. The PowerShell's just my way of playing with the DLLs to get an idea of what may be going on under the covers / to try to see if the DLL can loaded correctly / etc. i.e. it's a way for me to poke around.