922B-Stray Set Screw in Transmission Oil Pan

Hello

As I was changing the transmission oil on our 922B, I found what looks like a set screw (picture attached) laying in the bottom of the transmission oil pan. 

I'm hoping someone here is familiar enough with the innards of the 922B Range Selector and/or Transmission to tell me if they recognize it, and hopefully where it belongs.

I've been looking through the range selector parts drawings, and the closest thing I can find is a screw used to retain the spring and steel ball used to add detents to the forward/reverse control input shaft, but the forward/reverse control feels like the detents are working. Maybe the spring is just pressing on the range selector housing now?

If it is just the detent spring retainer, I'm probably not going to worry about it...

Any help appreciated!
Thanks