Getting started: I, having done this a number of times, budget about three to four hours to do this task. I've done it in two hours with everything going well. Sometimes you find the exhaust nuts are frozen on. Sometimes the universe is just not going to let you get that keeper/clip on the timing chain until you have REALLY demonstrated you want it. And so on. First time? Four hours: minimum. I would place this in the "advanced intermediate" catagory of dificulty.
Change oil if it is nearing that time. Turn engine to Top-Dead-Center. You have to clear