Hi Bill. I've been upgrading the same Mint for years, and sometimes a 'fresh install' is needed. But I have a menu link to my Win10 laptop going way back in the Mint's history that I don't think I can replicate and don't want to lose. In my Mint menu is a Win10 button that I click and a big page opens, no password needed, to everything on my upstairs laptop.
If there is no easy upgrade available, I do a very special 'reinstall'. I assume you would have to do one step at a time. BUT I
1. Use the Mint tools to produce a bootable usb stick
2. Use the same partitions exactly, in my case /, /home/, /swap.
3. Use the exact same passwords,
3. I DO NOT FORMAT /home.
Program software needs to be reinstalled but the data for these programs will be sitting comfortably in /home.
Besides regular upgrades I have done this install-upgrade combo twice.