IE Webbrowser control: How can I print HTML to XPS without GUI/user interaction?

On our .NET 4.0 web application project I got the task to provide ASPX content as PDF.

Current HTML to PDF converters lack correct presentation of the content, particularly when CSS 2.1 is involved, so I want to follow this path:

1. Server.Execute() the ASPX content to a HTML file
2. Open the file in the IE Webbrowser control
3. Save the file as XPS document
4. Open some .NET XPS to PDF converter
5. Return the PDF document

Here's the current challenge I'm facing: How can I have the IE Webbrowser control print to XPS without any user interaction? (Setting portrait/landscape mode, XPS file name etc. by code)