New here and have a question

Yes it does matter how the pistons and rods are installed. On all 4 corners cylinders the small valve relief on each piston in those positions needs to be to the outside because that's where the ex valves are located. The 4 center cylinders the small valve relief needs to go to the inside of the the cylinders thus once again that's where the center ex valves are.
I know the rods but I see he has an arrow drawn on the pistons like they have a certain direction they had to be installed on the rods. He might have thought the odd # cylinders were on the passenger side of the block and the evens #'s on the drivers side.