I dont think the 2000 Crown Vic's had the PI heads.
I'm pretty sure they didnt get the PI heads until late 2001 or 2002 some time. About the same time that the F150 trucks got the PI heads. May have been as late as 2003. I would need to look it up but dont feel like it right now.

PI heads will have a prominent 'PI' stamped on them.

And even then,.. the PI motors in the crown vic were rated less then the Mustangs due to intake and exhaust differences then the Mustangs. I am not sure if the cams are different or not. In order to match the Mustangs HP ratings,.. the upper and lower intake would need to be swapped with those from a Mustang and an aftermarket 'Mustang style' exhaust would need to be used.

And even then,.. in a heavy car like the Crown Vic saddled with an automatic it will still be a pig in NA form.

Hurst

Hurst