Regarding the advanced technique for crankshaft removal. I am pretty sure this is correct and it might be a good note for the write up.
When a four cylinder engine is at TDC two pistons are at the top of their stroke and two are at the bottom of their stroke. When the camshaft is rotated 90 degrees, the crankshaft is rotated 180 degrees and again two pistons will be at the top of their stroke and two will be at the bottom. Like the TDC position all the valves will be closed in this new position and it will not be necessary to force the valves open when the camshaft is placed in to position.
Regards
When a four cylinder engine is at TDC two pistons are at the top of their stroke and two are at the bottom of their stroke. When the camshaft is rotated 90 degrees, the crankshaft is rotated 180 degrees and again two pistons will be at the top of their stroke and two will be at the bottom. Like the TDC position all the valves will be closed in this new position and it will not be necessary to force the valves open when the camshaft is placed in to position.
Regards