[AJD] Hitch question

[Cotton Family]

As I spent all day sandblasting my 801 hitch that goes on my 70, and
worked on the lower draft arms to straighten them up, I noticed the 2
thin tabs that are on the outside of the draft arms.. I know the inner
ones work with the center brace stuff but what uses this little thin tab
on the outside.. I noticed in the ops book on the hitch that a small pin
clip is installed in the drawings but nothing else.. Anybody ever seen
an application where its used for something?
 
Dennis