Step by step guide to ignition timing?

[mr.bishi]

This gets stranger......my mistake on this,but the timing marks are actually lining up on 2 and 3 firing,it was 3 i was using,not 4. That's why i can't see it on 1.
Is there anyway the crank pulley can be put on 180 degrees out? Usually they just have one keyway?

I can't get my head around how else this can happen and the engine still run??