Cylinder head replacement?

Hi,

I have a friend who has gone through really tough times from losing his son to ending up homeless. He's been working hard to get back up on his feet and has been slowly. He has the vehicle listed above which has a lot of sentimental value to him that a family member passed on to him when they passed away, that broke down. He took it to a shop and was told the heads were cracked. He came to me asking if I could help him fix it. He said he can't afford what the shop is charging him. I told him I've never done any mechanical job like this on any car. I have basic knowledge and skills when working on cars. I myself am going through hard times too and even though he's just barely getting by he took me in and has been trying to help me get back on my feet too. So, I want to give back for the help he's been giving me and want to know how difficult it would be to do this job. Can someone help me out by providing me with the procedure on how to go about this? I would greatly appreciate any help.
Hopefully I'll be able to do this for him.

Thank you,
Rob