What is the correct method for installing piston rings on a piston, and how should their ring gaps be positioned before inserting the piston into the cylinder?

1. Stagger the ring gaps at 120-degree or 180-degree angles relative to each other, ensuring no gaps align with the piston pin or thrust faces.
2. Align all the ring gaps on the exhaust side of the piston to allow combustion gas to escape easily.
3. Align all the ring gaps on the intake side of the piston to optimize the air-fuel mixture flow.
4. Position the ring gaps directly over the piston pin axis on both sides of the piston.