I think you will see if you flip the flywheel over, that the magnets will pass the coil the same distance Before Top Dead Center going the opposite direction than they do now. Stick a pencil in the spark plug hole, and rotate the engine normally while watching the magnets/coil, and monitoring the approaching top dead center position of the piston with the pencil resting on top of the piston. Then flop the flywheel and do the same turning it in the opposite direction. It depends on how it was designed. If the magnets are in line with the keyway, this won't work. In this case, any good machine shop should be able to machine you a new keyway in the flywheel. My other worry is that often the magnets on the flywheel are placed more towards the front or rear on the flywheel, and they may not pass the coil properly with the flywheel flipped.

Let us know how it works out,
AV8TOR