1-2 Accumulator

I was in the process of replacing the 1-2 accumulator in my 97 Mark VIII. Thanks to the indepth instructions I got on markviii.org everything was going well. While I was completing the job and found a plastic piece (looks like it might be a check valve or something like that) in the old tranny fluid. It looks sort of like a mushroom with an o-ring on it. I was replacing the filter at the same time. I took the new accumulator and filter out but the part does not seem to go with either one. I don't dare put everything back together without finding the proper place for this part. It has a part # (K 351-3 3) on the inside hollow of the mushroom cap. Any help with this would be greatly apprecited. I can email photos to anyone that thinks they can help me.

I've looked all through my Ford service (shop) manual for the 97 Mark VIII and could not find anything that even looks like that part in any of the exploded views or any other diagram. Can anyone help confirm this?

Several years ago I went through the same thing wondering what that part is. It is actually the plug that they put in the hole where the fluid dip stick goes. During assembly of the tranny they use this plug just to keep dirt or debris out of the tranny until it goes in the car. Then when they stick the tube or stick in it shoves that plug into the tranny just to lay in the bottom of the pan. So you can throw it away & not worry like I did till I got an answer.

Gene