I'm back. After perusing a thousand other themes, I decided that I just like Atahualpa best. So I successfully uploaded 3.7 per your advice, thank you, and it's working.
But now I have to return to my previous issue: the location of the Header file.
You say: "All header images are located in /wordpress/wp-content/themes/atahualpa/images/header/."
Looking at my directory I see: /wordpress/wp-content/themes/atahualpa/js/header/.
Swear to god I'm not making this up. Header file is definitely located in the JS folder. When I put jpegs in this folder one week ago, it broke my theme and I had to default to 20-10. I don't want to break it again, so please advise on where I should put the pics.
Thanks a bunch.