I have a house that dates from 1949. The original interior door hardware is still here: Yale lock sets with push button locks. Most are in great shape, but a few need to be replaced. I can't figure out how to remove them, and a local locksmith spent over three hours trying to remove one. I reached out to the Yale company, but they were of little help as they could find no information on their products from that time period (hard to believe). In fact they suggested that I would need to take the door down and remove the lockset with a torch. Any help would be greatly appreciated.