Some help with gear pattern?

If the chuck was just a used open deal, there's nothign wrong with the pinion - right up until you take it out of the case. Then you are into the "rebnuild it all" deal. I would re-do the carrier a few times first and see how it goes. I've done what you're doing many times - you don't cause problems unless the ring gear and carrier do not go exactly back where they were.