Farmall Cub

I have a 1949 farmall cub with a sickle blade on it. The end closest to the tractor is dragging the ground when the part farthest from the tractor is about 2-3 inches above the ground making it bounce up and down. I don't know what to adjust to stop this.

go here to see the mower manual. http://www.cleancomputes.com/Cub/Cub%20Implement%20Manuals/Cub-22%20Mower%206-17-52/index.html

check this page. I think this is the adjustment.