Are you asking about the 4.6L? They're all the same, swap away. They also make 4.6 to 5.0 and 5.4 upgrade kits. Panther platform is pretty much very versatile. I would keep such swaps within model years tho.
Yea the 4.6L V8
If you're swapping in another 4.6, you won't have any problems, you may need to swap over the computer too, or reprogram your existing one. (that wouldn't be necessary if both engines are identical in options).
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