My iTunes files are on an external drive - how do I move them into Apple Music in Big Sur

I got there!

1) Opened Music and went to Preferences -> files

2) Changed the Music Media folder location to a place on an external drive with lots of space

3) I said yes to "Would you like to move and rename the files in your new Media folder to match the "Keep Media folder organized preferences?""

4) Went to File -> import and pointed to the top level directory that contained a huge number of music (in iTunes) and podcasts at lower levels in the directory structure

5) in about an hour it had imported nearly a terabyte of files

6) in another hour or two it completed some cleanup activity (like Determining Gapless Playback Information whatever that is)

Now I need to figure out playlists, smart playlists, Genius, and some other features and structures...