Here is the process for timing a mag.
1. Remove #1 spark plug. (front plug on engine)
2. Place finger over spark plug hole.
3. Turn engine until pointer is in line with notch on flywheel and compression is felt. If flywheel has 2 notches align pointer with second notch
4. Check mag coupler for proper alignment.
5. Install magneto and move against engine block.
6. Turn engine 2 revolutions until it lines up with the pointer once again.
7. Slowly rotate magneto away from engine block until a distinct click is heard.
8. Tighten magneto. Engine is in time.