I've had it with this 904, about to give up!

If the surface in the circle on the right is flat (can't tell in the pic) and you put that ball back in the hole circled on the left and stake it in like the other two are, I run that puppy.

You dont even have to worry about the surface around the balls much.
That ball is just there to plug the hole where the factory drill bit went in to make an oil port.

The ball is just a plug.