If you can move the hub anywhere before tightening it down your all set.
Set the hall sensor at 28 degrees BTDC.
Then put the magnet on the left side of the hall sensor so you can see the whole magnet.
Just the outside edge of the magnet should be next to the hall sensor.[right side of magnet against left side of hall sensor.
Then check with a degree wheel and see for sure when the plug fires.
The hall sensor triggers after the magnet has gone past the sensor.
Go to chignitions for a downloadable degree wheel and instructions.Thats the man to see.