DOORS with GCM - managing duplicate requirements

We are receiving two sets of ReqIF files from a partner where a lot of the requirements in each set are the same, but about 20% of the requirements have different attributes, primarily Primary Text.  The requirement IDs in the two sets of files are about 99% identical, even for those with different attribute values.  I thought with GCM, if I created a component and copied from another one that they would share the same IDs.  I thought in this way, I could import one set, copy into a new component, and then import the second set in the new component and the IDs would match between the two components for the most part.  So that we wouldn't have to maintain a large set of duplicate requirements.  Any ideas here?  How can you share requirements between to components in GCM?