Cylinder Head wanted on engine rebuild

I got a 1989 B2600i 4x4 5 speed. My old head is cracked in 2 spots, between valves. Typical overheating, and still driving. Totally warped it. I need a new head. I just took the engine out yesterday. Took some time. I thought I missed a bolt or 2, but engines are probably normally stuck on tight. I had to use a truck jjack to help it out of trans. Of course with all this rain, the block is abit rusted. Nothing a machine shop can cure.

Since I got the engine out and on an engine stand, what are some tips you can give me. I am a complete newbie to rebuilding engines. What are some extra steps I can do to make it a easy job

I started the tear down, writing a ton of notes. Putting every bolt in a large paper envelope, with notes and where it came from written on it.

Just wondering what the hell the 2 shafts are, on either side of the crankshaft? They have notches on the sprocket that line up.