DOH .. you beat me to it Johnie...
I was just going to say....
When you tighten the top nut down it puts pressure on the broomstick which holds the inner parts keeping them from turning, for when you remove the allen bolt on the bottom. Otherwise the insides will turn along with that allen bolt.
Some say an air impact gun
usually works, but I don't have one handy at home and the broomstick method has worked for me every time so far! (3 times to be exact
) Twice the allen bolts we're badly locked and stripped (but not completely)
And of course a good soaking first with penetrating oil. I did have to put a little breaker bar on the allen wrench... but that easily unclamped enough to hand turn 'em the rest of the way out.