transmission on 2002 Mercury Grand Marquis

Was changine transmission fluid to try to help a shudder that happens when going into overdrive - - - found a plastic valve and o-ring in pan when pulled it... Where is that from? Trying to figure out where it goes... thanks.

Asked by for the 2002 Mercury Grand Marquis
The white/yellow plastic piece is a shipping plug, used to block the dipstick hole when the transmission is shipped to Ford. When the tube is inserted at the factory it falls harmlessly into the pan. Discard the plug.
thanks so much!