the p75 head has a different intake manifold bolt pattern. the bottom bolts are the same but the top bolts sit higher.
you would need to ally weld extra metal to the original manifold.
theres also no place for a mechanical fuel pump. you would have to make the hole in the side yourself, and machine a lobe into the cam. alternatively you can just use an electric solenoid pump.
thats the only issues you would have.