Importing a Mopar from Canada to The USA

You should be able to have any reputable vehicle transportation company and customs broker manage the deal for you, for a price. I have brought vehicles up into Canada myself, without a customs broker, but the last time was 2011, things might have changed.
My asshole brother did sell a car to an American buyer, and he transported it across the border himself, but I don't know all of the details. I doubt that it was overly complicated, because he wouldn't have done it if that was the case. I do remember that the funds had to be transferred to him before he was allowed to move the car across the border, and he was required to show proof that he had received payment in full before.