Looks like the story is 90 percent BS to me.
I'm having trouble figuring out why the Grandson is owed the car, why anyone would change the fender tag but not the VIN if trying to hide the identity and why we are supposed to believe the car was stolen in the first place.
Back in '82 the car might be worth $5000. The only reason it's a big deal is the perceived value it has now, the "legend" that grew up around it and the fact that Christopherson might have screwed around on the phone.
I think there is something else to the story that has not come out yet. If I paid $35K for a car with a clean title and unaltered VIN I would tell the police to go pound sand.
Dead original owner, "Famous" stolen car with no Police report and a Grandson that thinks it's his for some reason.