They make a slide-hammer with a vise-grip attachment. I got mine off of amazon.I had the same problem with a ‘68 18 Evinrude. Clamp it above where the water pump housing goes.
I have a mid 70’s omc outboard with no spark . Don’t know the brand because it’s been painted. Model # 50RL78S. Coils checked good with a Merc o tronic. There’s no continuity from the two leads coming from the stator. Any help will be greatly appreciated.