It IS easy, Tommo. Do a Google search for "ConvertLIT" and download it. Once you have it, run it to convert any LIT file into its "Open eBook" source (a folder containing HTML files, images, and an "opf" file to "glue" it together). Open the "opf" file in MobiPocket Creator (free download from
http://www.mobipocket.com), click the "Build" button, and you have your MobiPocket book.