I dont know.
All I remember from autoshop is that you are supposed to calibrate your torque wrench's before each use, I do not remember how we did it, that was a long time ago.

 

Here's an exploded view of tranny and all the parts, which all look like they are mostly round of some size.

 

Nice find. The only part I can see that resembles the spring I have would be the "Linkage 991" on the bottom row. I think it could have broken off from there.

Edit
But isnt that linkage on the outside?

 

being wound that tight I would think it is from one of the seals around the input or output shaft. You may see it leaking fluid from there is it one of those. The outer of the seal is still a hrad metal so it may not be leaking a lot. If you see it puking it's guts out then you need to drop the tranny. The good nes is that they are easy to replace once the tranny or TC is out. Good luck, let us know what else you find out.