There are three versions of the 800 hitch, 800, 800a, and 801. The 800 has the large adjusting crank on the right side. That crank was replaced on the 800a with a short lever on each arm for adjustment. The 801 has the torsion arms to transfer weight to the rear axels. Over the years what you usually find is a mixture of the three.
The 800 3pt hitch was not designed for the letter series although many use them without problems as I have.