Camshaft Interrupter Magnet on 1990 Buick LeSabre

When installing the interrupter magnet onto the sprocket through the camshaft sensor hole, which way does the magnet go in? Does the brim go in first, or does the magnet go in first?

Asked by for the 1990 Buick LeSabre
The magnet goes in through the back of the cam sprocket. The timing cover and chain and gears will have to come off.
Thank you, but the car was fixed back in June.