I worked at a Pontiac store in the 80's. We would drive the car in figure 8's after a limited slip rear service. That would work the additive in to the clutch plates.
So, I'm thinking you walked into that Dodge store to buy a used Plymouth and the salesman said, "Why buy used when you can buy this new Dodge for the same monthly payment?" lol
Awesome car!
Sorry to hear of your woes but it says a lot that you got custody of your son. As for the swap, my opinion is leave it alone and let your son hone his driving skills on a docile car until he gets behind the wheel of the wagon.