You now own the car outright unless there was a provision to the contrary in your Judgment for Dissolution. Don't worry about the title since your name is on it. Insure and pay to license it. The insurance and license will now be in your name. I am sorry for your loss.
Who was the car assigned to in the divorce? If it was assigned to him and you never transferred it to him, you might not be in compliance with the terms of the divorce judgment. If there are heirs to his property, they may or may not make an issue of it. For the purposes of the registration and ownership, using the death certificate to transfer the jointly owned property will be sufficient. If the estate comes after you, you may need to turn the property over to be in compliance with the divorce judgment.
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