190XT series III engine value

Back in 2018 when my Dad passed away, all of my siblings were either indifferent (didn't care) or chomping at the bit to sell off his 1966 190XTD he had owned since 1970/1971. My Grandpa bought it FOR my Dad when Dad joined him on the family farm. When Dad sold the farm in 1989, he kept all of his AC tractors (10) just to have and to fiddle with. Later on, as his health deteriorated, he sold most of them off 1 by 1 until just the 3 "original to the farm" tractors were left. In 2015, we had finalized the deal that gave me the WD and WD45. It was always my desire to keep the 3 together just as Dad had done and he knew that. As we all surrounded him during his final days, he made the decision that if I still wanted her, then she was to go to me-period. All of my siblings and my step-mom too easily accepted and then also honored his decision on this and I will forever be indebted to them for this kindness. Most of Dad's other stuff was sold off with the proceeds going to our step-mom. The last "work" that the XT did in NY was to move the few remaining pieces of Dad's equipment to the local auction yard for their next auction. As I made those four round trips, I did ponder the idea of leaving her there too rather than having to deal with getting her hauled down to KY like I did the other 2 a few years prior. After that last haul, I had a quick chat with the auctioneer (who knew my Dad well) and asked him point blank what he thought the XT would bring on his auction. When he said he would be surprised if it went over 3K, my mind was made up for me. He also went even further to suggest that since it was a family tractor, don't let it go anyway. I knew that Dad would never sell it for that much and neither will I. The auctioneer even helped me with a contact for a hauler and 1 week after running NY roads hauling equipment, the XT was getting unloaded at my house in KY. My wife and kids do not have the time with and attachment to the XT that I do. They have my permission to sell it for whatever they can get out of it after I'm gone but it won't leave 1 second before that time.