My 98 Windstar recently threw a rod. I know that the Supercoupe uses a variation of the same 3.8 Essex engine. How feasible would it be to swap the supercharged v6 from the Thunderbird into windstar?

 

Since both engines are the 3.8 Essex engine, I would say that it's doable, But you would need to verify engine clearances. You would also need the computer and wiring harness from the donor T-Bird for the engine. Since your original engine has 200 HP and 230 lb ft torque, you would only be gaining 10 hp and 85 lb ft torque over your stock engine, but would have bragging rights for the S/C under the hood.

 

The T-bird has the engine in longitudinal orientation and the Windstar across. I would check if there are differences between the two variations such as the location of the oil pick up or baffles in the oil sump.