How to migrate Creo Diagram template and Symbol library to Creo Schematic?

Discussion - "Import component library in schematics": https://community.ptc.com/t5/3D-Part-Assembly-Design/Import-component-library-in-schematics/td-p/169364

As was stated in the other thread, you can set use Creo Schematics to import full designs from Diagram and you can also import symbols that have been exported with one of the common exchange formats.

I have tried both and found them to be horrible failures.

Used DXF to import from another software package and got so much garbage that couldn't be cleaned up to make good symbols.

Used the built in import for diagram designs.  Our Diagram designs did not have components, just connectors for the harness.  I had hoped that we could bring them in and replace the connectors with the components and arrange them to look properly.  This would have been a great way to bring in old designs for modification.  It came in but with nothing on any kind of standard grid (metric, decimal inches, fraction inches) that I could find.  Would have been a massive amount of work.

We decided that it was time to start clean (lots of garbage symbols created over the time the other software was used) and came up with an agreed on style of symbols that was primarily based on the old system.
Once you get a hang for the basic parts of the drawing tool in Schematics and connecting the data, you can knock out items relatively quickly and end up with a better looking and more useful catalog.