More years than I wish to think about but there used to be two C-97s in MIA. Both with dark blue tails. The owner tried to get them listed as Stratocruisers but the FAA said the airplanes differed from the certified pax birds and there was essentially no way in hell they were going to sign them off to fly pax.
I heard that later on, the birds were registered in Central America and were used to haul freight. The story was that coming out of Mexico City with a bunch of horses in the back, one or two engines failed. They were near gross so it was evident they were not going to remain flying machines. The old -97 went in with most of the horses and one or two of the crew not making it.
But the FAA seems to be a bit funny about old warbirds carrying pax.. even if it is a good old machine like the -97.