A833 shifter plate removal.

Get something for a big punch, even a big 1/2 or 5/8 bolt, and just about the largest hammer you own and give each a good swat on the head. If you (and I am) afeard of hitting your hand, hold the thing with vise grips.

If that doesn't work, HEAT. Even a "prop pane torch and prop pane accessories" can break them loose.

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