How to convert configurations to BOM in order to implement Asset Based Ordering

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We are looking to implement ABO.  The implementation guide states: Set up BOM Mapping Rules and implement a BOM for each configuration model used to create assets.     I have a couple configuration models using BOM mapping, but the one used most often is not BOM mapping - it's recommended items.  I'm looking for ideas on how convert my existing configuration to BOM mapping.  We have thousands of items.  

thank you