John has it right . . . there won't be much, if any, respect for new procedures so it is important to determine what pieces of ISO 20000 SMS you already have in place. Take the standard, go through it and start checking things off the list and/or reference what's already covered. I'm going through an ISO 20000 SMS implementation project now and, considering cultural differences and people being people, this is the best avenue to take IMO. The QMS will integrate the SMS, with a basic SharePoint (file structure-like) management system set up with categories that will show documents fulfilling 13485, MDSAP, 20000, etc.