A mother screwdriver, really liberal WD-40, and a bit of heat, and they'll come right out, easier than you think. I couldn't budge them with anything until I applied the heat. For installing new seals, I used a bit of PVC pipe--I think it was 1 1/4", coulda been 1 1/2" . Goes in easier than it comes out.
This was on a '75 CB550F.