Wheel bearing grease is far too viscous – especially at low temperatures. Consider a low temperature lithium grease.
Ensure all surfaces are clean, dry and especially have no grit on them.
Apply thin coats to:
o the inner surface of the crankshaft hole,
o the underside of the mag plate where it rides on the armature support plate, and
o the top of the retainer ring.
While you are in there, give each points cam follower pad a drop of light machine oil.