I've done the entire 4l30e.
I can't remember each washer and where each one goes exactly, as it was a few years ago.
But I can say that 99% of them are the plastic thrust washers. I ordered everything before I tore it apart (including a few of each color washer). Each color is a different thickness and you put X color in according to how much wear the parts have and how much play the assembly has.
They are fairly cheap. Just remember to use some assembly lube. It makes life that much easier
The rebuild kits do not include the washers. It had mostly sealing rings, clutches, a new band, a few bushings, some valve body filters, etc.
If you have any questions about it, I can hopefully answer them.