Just looked at the assembly instructions, I can say for certain that neither of our assembled transmissions has that spacer plate in it.
I will have to check when I get to our meeting tonight if they are with the "extra" parts from when the transmissions were taken apart to assemble into the 2-1 kit. Am wonder if that spacer plate is getting stuck to the block you remove and we just did not notice it.
Just a suggestion to pass along....In the assembly instructions, it might be a good idea to make a bigger thing of making sure that spacer is present. The wording is at the end of a small paragraph and might get easily overlooked.
Seperating it out into its own bullet would make it harder to miss.