Working for GE Commercial service years ago .I’ve removed quite a Few Agitators by Simply Spraying a small amount of WD40 in the Agitator Post Spline’s . Let it set a bit . And then using my Large (Rubber) Hammer while Lifting from the Bottom of the Agitator Base , Gently Tap around the Top of the Agitators Head . And it should just Pop up . The longer you let the WD40 soak in, the better .