Want to see this?
Go to the setup folder and open this file (using Notepad):
In the file find (CTRL + F):
#============= DOTNET Begin ===============
Under it you will see:
Copy it and paste it here:
Save the file (CTRL+S) and your done.
(Doing this may or may not violate various agreements you have made or will make with Autodesk of which I may have just taught you how to do but do not endorse).
You should already have .NET installed with Windows 8 by default, so no harm done. This should also work for other Autodesk products.