High Level
Extract data via sqlite into a file.
copy that file to a location on the linux box.
find the library DB in linux
/var/lib/plexmediaserver/Library/Application Support/Plex Media Server/Plug-in Support/Databases
Install sqlite on the pi
Execute the setting file created, i got a few errors based on stuff already in the DB but for the most part it looks like the bulk of it has worked.