I haven't made any further effort on the project, for several reasons that don't need to be discussed on the open forum. I would be happy to communicate by PM with anyone who is interested, however. I'm still convinced it's a viable option, and MUCH less expensive than having a 50-something year old damper rebuilt or modified. I checked on the availability of the parts on Ebay a few days ago, and the cost is still well under $75.00. That leaves quite a bit available for custom machining in case someone doesn't have access to a lathe before the cost gets prohibitive.
Jerry