I've got a part that's been used for 10 years and is in thousands of assemblies. I want to create an updated version of the part from scratch - it's similar but needs to be modeled differently than the original. I want to be able to use "Replace Components" in my assemblies - swap in the new part and keep the mates.

I understand that I can name the faces, and I've named the important ones identically in both the old and new part. However, the mates break when I use Replace Components. It seems like the mates maintain a reference to the old face name / ID despite my having renamed the faces.

Example files are attached. Replace component 'old socket' with 'new socket' - even though the mated faces are named the same, the mates break.

If for example I mate 'old socket' AFTER I've named the faces, and then Replace Component, the mates work. Could somebody confirm this, and is this expected behavior?

Before you could rename a face (back in 2011/2012 maybe?) I had come across a way to get the internal name that SolidWorks assigned to the face. I believe that somebody even created a macro to change that name.  If I could get the internal face names, maybe I could use those names in the new part and the mates would work? Is there a way to get the internal name? Using "Face Properties" just gives a blank.

Any help would be appreciated. Thanks,

Brian