Rockwell jointer question

[Rockville Ken]

Greetings,

I recently purchased an old(?) rockwell delta jointer, model 37-220 that is in excellent condition. I took the fence locking mechanism apart to clean some rust off, and now I'm having some trouble getting it back together properly. I think it may be some issue related to something called a "segment key", shown as part # 58  in the exploded diagram attached.

Can anyone tell me what this "segment key" is supposed to do, and whether is is supposed to slide freely in the groove it is in??

Thanks!

[JGrout]

The segment key is supposed to interface with the angling (curved) slot in the fence head.  it is supposed to be mounted in the static section of the mount you may have to take a file to it or maybe just oil it to help it move around the curved slot.

This is an edit ignore what I said before this edit; the segment key is the half round part not the screws adjacent to the head that I thought were the pins. 
Joe