There are 26 total M10 head bolts. Make sure you have all of them removed. Then there are two smaller bolts at the front of the timing chain cavity, AND there are two more bolts that also attach the fuel filter bracket. But with those 30 bolts removed, the head should pop off with minimal effort. All the bolts are shown in the sequence in the PDF above. Print that out and bring it with you as a guide.

Either cut the timing chain, or use a stack of spacers/washers with a bolt to pull out the rail pins. Since this is a junkyard engine, I'd cut the chain, and mess with the rail pins on the workbench.