I've never seen a two wheeled one. It is very basic. Not many adjustable components. Gallion was the big name I've seen American Road Machine built both towed, and transformer style incorporating farm tractors in the frame. I've seen 30 miles from home, a Farmall M. It has extended frame with a multi adjustable underslung blade. I was buying a Christmas tree this winter, and spotted a Caterpillar towed four wheel leaning wheel grader.
Lots of small towns had them. They didn't necessarily have machines to tow, so they contracted the tractor.
Willie