Them-there pesky stuck agitators...
To get the one out of our 512, (of course, after asking the gurus here), I ended up rigging a sort-of "sling" out of two loops of fairly thick nylon rope, by lacing the rope through the holes in the bottom of the agitator that you see when you look down the center after you've got the lint filter out. Use two loops, one on one side, and another on the opposite side, and loop the top of the ropes around a section of 2 x 4 before you tie them off, and use that 2 x 4 as leverage to pop the agitator up and out. Hope that's at least as clear as mud. As Douglass Adams would say, "Go to it, and Good luck." Oh, yeah...and wear yer hard hat! ;-)