Since you don't have any end shake, an alternative to removing material from the extractor boss would be to remove a small amount of material from the end of the yoke barrel. You could use a piloted facing reamer to clean up/true up the yoke barrel end. (removal of .001"-.002")
This would free up the cylinder assembly some by moving the cylinder forward a bit. You would still have to remove some material from the barrel extension, probably .003'-.004", to open the barrel/cylinder gap back up to around .004".
Carter