95mercxr7

i have a 95 merc xr7 that i would like to get more umph out of i mean beater breathing from the heads. what i am asking has any one used heads off of a 01-04 4.6 v8 2v mustang heads on a older 95-98 4.6 2v v8. to help it breath better. other than diferent valves port and polish and cams as well as a super charger. what i am asking is there any issue on putting different newer design heads on a older long block i just wanted to ask to see if some one tryed