Ed,
I'm going to say this only once.
I find it very hard to believe that you really pulled 3tons behind a MarkVIII.
That being said.
If you really did, I am personally calling you a moron. I pull 6,500 behind a half-ton GMC truck very frequently, and can tell you that a uni-body chassis is NOT designed for that stress. And for that matter.....where did you find a minimum class 3 hitch? If you were pulling that with a 1 or 2, the DOT in many states would impound your rig.
Sure the car has the power to pull it, but if you had to make an emergency stop OR manuveuer........it would be BAD. I'm not even going to get started on braking.
If I saw you out on the road with that death trap, I'd have the cops on your ass so fast your head would spin.
Quit being a stubborn moron and take good advice while you, (and more importantly), everyone else on the road is still alive.
Mike