I will assume you mean front to back instead of upside down. It won't mount otherwise. The coil armature must still face the flywheel.On the Briggs mount the coil upside down.
Kash
The early engines are N-S-N and late are S-N-S.
I'll offer this to the Simple tractor forum as this advice has never been offered in the many years I have been a member. The factory no longer regausses/repolarizes flywheel for the public. I will end up makeing my own B&S flywheel gausser armature and do them my self. I have/own several engines to do.