3/8" ball & spring 727 tranny help

[carsnguitars]

Okay so I had a small leak and decided to replace the seal.
Pulled the throttle body out and this 3/8 ball came out on the ground, not sure how?
Anyways, according to the pic attached this is where it goes.
I open up the plates, the other balls are in place but this one was missing.
It mentions a spring, I cannot seem to figure out how this ball goes in with what spring, there was no spring

Anyone have exp with this can point me in right direction?? Btw, it drove and shifted before just had a leak.
I have 2 books and still cant seem to find this spring and how it goes....

This board always seems to have great insight so turning to you again...thx guys.

Update: found a pic online looks like ball sits on a spring that you have to careful balance to put the lid back on.

[John_Kunkel]

In the pic above there is a spring in the casting below the ball; that ball/spring is a pressure relief valve, if it's missing there will be a wide open pressure leak. Check to see if there is a hole in the steel separator plate that the ball fits into, if there is a hole you will need to find a spring and replace the ball. If there is no hole in the steel plate the ball isn't needed.

If the valve body was assembled from mismatched parts or if the valve body has an aftermarket steel plate the hole might be missing.