You can convert unstructured FrameMaker files into structured FrameMaker files using Conversion Tables. With Converstion Tables you can map paragraph styles, character styles, table styles, variables, cross-references, markers, and images to corresponding XML elements.
FrameMaker provides a mapping feature to help you transfer your unstructured documents into structure. Your results depend on the following factors:
Document consistency. Documents that implement a formatting template consistently, with few or no formatting overrides, will convert better than documents that are full of overrides.
Similarity between unstructured and structured documents. A new document structure that is similar to the organization in the unstructured documents eases the conversion process.