Changing Starter Gear, How Do I Get The Lockring Off?

[Squiggle Dog]

I am putting a turbo starter in my 200D and I realized that the starter gears have a different number of teeth. I have to put the gear from my old starter onto the turbo starter. I have both starters partly apart, but I cannot get the gear collar off because of the lockring.

How do I remove the lockring? I've broken some tools and even tried to make my own, but I can't get the dang thing off! Any ideas? Now every auto repair place is closed for Christmas. I can't find any information anywhere about how to remove lockrings. I guess I'll work on installing the fast glow conversion kit...

The first pic is the collar of my the 200D starter. The second pic is the collar of the turbo starter. They both have a snap ring. I have to remove the snap ring so I can remove the collar so I can swap out the gears, only I don't know how to remove the lockring.