Good little gadget!
Mine had not been removed for years. The RHS needed a huge effort but moved in the end. Used a combination of a timber wedge, rubber mallet and much arm pulling power.
Not sure if this is going to help for next time but I smeared a film of copper grease on the splines.

 

Good idea on the antisieze.

 

I used a small tie rod press to grab under the arm and the screw presses on the shaft. A couple of turns and poof. Its off