I found this in the tranny pan after loosing reverse.Drives forward ok an shifts ok.

What do these look like they went to?

 

Looks like a snap ring that retains one of the clutch packs.

 

Is this why nothing happens when I shift to reverse,it's automatic 6 cyl 3.9?
Has that broken clip caused overdrive clutch pack to move or not enguage in reverse?..
There is a slight wine in low gear too.
Can I pull the overdrive without dropping tranny fully.?

 

Yes that could be the issue, I am pretty sure you can pull the overdrive housing off with the transmission still in, I just did that to a 47RE not to long ago.

 

Overdrive auxbox shouldn't affect reverse. It's probably the retainer for the reverse primary clutch.