These are OEM toploader 4-speed service parts which I purchased in the 1990’s which are no longer available through Ford.
*4 new blocking rings (C4AZ-7107-D)
*1 new and one used (to show contents of kit) small parts kits (C4MY-7B331-B)
*1 package of 2 new thrust washers (C4AZ-7119-A)
*1 new tail housing bushing (B3TZ-7A034-B)
The blocking rings, small parts kit, and the thrust washers fit all versions of the toploader; 28 and 31 spline.