When editing a book individually, in Calibre, there is a second tab for custom data. It just has ASIN and location. I spent a bit of time searching Amazon and putting the right ASIN in all of my books, 297 to be exact. Is there a script that will move that ASIN from that part of calibre and put it in EXTH 113, replacing the UUID? I would rather not use fake generated ASIN or the UUID one since that is breaking the covers.
I know the world doesn't revolve around the Kindle, but there must be an easier way to do this.