Like stated above, the heads can be pulled off but it is a pita. Not like on an old pushrod motor. You have to take all the front accessories off, front cover, intake (all the stuff that goes with that) then you have to wrestle the heads out of the car. I am in the middle of a pi swap for a friend/family member and I currently hate him for it. (installing long tubes as well).
Take your time and label every bolt you pull out on little zip lock baggies to make reassembly quicker and easier. We did't label a few bolts it just cost us time on reassembly. Good luck.