This if a big and very important job. It requires more than you can get here at FixYa.com. You need many special tools not to mention a place to work. Do you have a garage you can work in for at least two weeks? You will probably have to get the heads worked on. Then there is the reassembly.

If you are serious about this, you need a motors manual for this make and model plus all the special tools and a strong helper.