Looking at the timing gear on top in pictures 2 and 3 you will see a little dot On that gear in about the one position. Looks like a circle.
Turn the crankshaft until that dot is down at the 6 position.
That should bring the dot on the small gear on the crankshaft into alignment with the dot on that big gear.
The dot on the top gear will be at 6 position and the dot on the crankshaft gear will be at the 12 position. That is if they line up correctly.