I finally got all of the leveler scraped off of the floor. It ran all the way to the wall. In that spot, it was thinner and I could remove it with a hand scraper, preserving most of the stain on the floor. In the scrapped area I had to use a large long handled floor scraper and it still was a ton of work.
It's a mystery why the leveler was even there. I took a long straight edge over the floor and it was only down about 1/8 of an inch. No reason to use leveler as far as I can see. This floor was carpeted when I moved in, and since have removed the carpeting. There are a few gouges in the wood, but if it's carpeted, who cares. Still no reason to use leveler.
I'll eventually have these floors sanded and re-stained. For now, the large area rug I'm buying will cover the worst of it.
If there are any hardwood floor restorers in the Kansas City area reading this, send me me a Private Message. (Click on CatBrat name above my avatar, then on Send a PM) This area is 286 sq ft in an L shape. There are also 3 bedrooms with HW floors, but I'm not concerned about restoring them, at the moment.