Blogger has an XML export and WordPress has a Blogger Import plugin that can read the export, so moving the posts over was generally pretty easy.
Everything defaulted as Uncategorized. There is a a bulk edit facility where I could *add* another category, but I had to touch each post to remove the Uncategorized tag. Once all the posts were properly tagged, I added a menu that lets me put all the posts from five separate Blogger blogs and use the menu to view only the specific subjects.
The other caveat to the export/import process is that images came across on the import as URLs pointing back to Blogger. I will need to copy those actual images over here and edit the links in the posts. I think I can massage the XML files themselves to facilitate it…
All in all, though it is not yet 100% finished, it was much easier than I expected, especially with 190+ posts going back 6 years.