Forget about the washers. Use 2 of the B020 bearingd instead. These kits are a little confusing. They have some of the newer items incorporated into them, and still have some of the older stuff.
It's like they had a surplus of older stuff and threw into the newer kits to get rid of it.
I'm still going round-and-round with HPI about using the older 3 hole version one-way and discontinuing the A496 pulley.