I want to move my catalog to an SSD drive on my PC. I currently have it on a spinning hard drive. Am I correct in my assumption that I only really need to move the LR6 Catalog - Main.lrcat file? If I only move that file, my understanding is that the previews will regenerate as I navigate to folders, is that correct?
I have LR6.
Yes that is correct. LR will generate previews on the fly. I did exactly that when I moved my catalog as the previews file/folder was quite large. I copied just the .lrcat file and double-clicked (control-click) to launch it. When selecting folders with a large number of images I found that I had to scroll with the sidebar but LR quickly filled the blank thumbnails.
Yes your are right. You need only move the catalog file to the new hard drive. But...., you spare a lot of time if you move the preview folder too.
Take a look here and refer section 4.