GAC Install a DLL using PowerShell

Installed assembly into GAC -

Set-location "c:\temp"
[System.Reflection.Assembly]::Load("System.EnterpriseServices, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a")
$publish = New-Object System.EnterpriseServices.Internal.Publish
$publish.GacInstall("C:\temp\Mydll.dll")
iisreset

To Get assembly info-
([system.reflection.assembly]::loadfile("C:\temp\Mydll.dll")).FullName