This is a tough one. Technically stolen property still belongs to the original owner. But if you need to use civil remedies to fix a situation you have to act before the time expires to use the civil remedies. For example, the Tort of Conversion which is taking over and using someone else's property, has a statute of limitations of 2 years. Also there is a doctrine in the law called "laches" which can be asserted to bar someone from a legal remedy by essentially saying you waited too long and too many things have changed and it would prejudice other people to allow you to go forward with your remedy now. Finally - do you even know if the car is still drivable or any where it can be found? You are assuming in your value estimation that the car was maintained and cared for. I would guess that a majority of cars from 1973 either wore out or got wrecked in a crash and one way or another ended up in a salvage or wrecking yard. So if you are curious about the car you will need to track it down first. If you still have the vin number you might be able to hire an investigator to run a data base search and locate where the car is today. Then you could report the car to the police as your long lost stolen property - and possibly you will be allowed to claim the car. (People that receive stolen merchandise don't normally get to keep it even if they were ignorant of the theft - but cars are a bit different in that they are registered via the title process which is supposed to give the next purchaser the right to rely on the title as being the true evidence of ownership. This purchaser is known as a buyer in good faith. While the title was forged at one time, you may have added to the chain of misinformation by not being diligent in reporting the theft and making sure that the title wasn't repeatedly passed on to other innocent purchasers.) Frankly I would just forget about the car and move on. It sounds like a headache that will cost you more than the car is worth to deal with.
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