Thanks. I don't install apps that fall directly under those categories but I did delete CCC (never used on my latest iMac), LastPass, TG Pro, Weatherly, Canon Camera Apps, Photos Extensions and a few others, restarting each time to see if Location Services stayed on but nothing changed.
Adobe has so many apps, sometimes 2 of the same running in the background and the Core Sync and Helper so I'm curious about those. Autodesk is another. I use mobile versions of Adobe and Autodesk apps that sync with my iMac - neither have full disk access. I deleted LastPass from Firefox, Safari, Chrome (and will delete Chrome and Earth to solve the issue) but nothing has worked far. The internal drive is an OWC SSD (it was installed when I bought the iMac from them) - trying to think of anything out of the ordinary.