I thought I'd share this for those who might be interested, in regards to the small pins keying the slipper plates to the input shaft, since I haven't seen it really mentioned since the discussion about the pins.
I received a Team Durango DEST210 stadium truck today as a gift. It also uses the "pinned" slipper plates. While the BZ-222 isn't a direct copy of the Durango DEX210, it does look like they share quite a bit of the same design.