Yeah, thought about that but not sure that helps. The plate is at a serious disadvatage force vector-wise. Think about how a telephnone line between two poles always sags ans impossible to pull it enough to get it perfectly horizontal. Thin light line (bearing back up plate) with gravity acting upon it (gear shaft) has way more mechanical advantage than the poles (outer edges fo case).
For the 555's, you can add some extra c-sink'd bolts to help. Thought I posted this back in 06 when the 555 went in my T2 Shadow