I ordered the repair kit for my model, which came with everything I needed except some grease. I pried off the top cap, pulled the inside cover out, used a socket on an extension to remove the bolt that holds it all together and removed the entire agitator assembly from the tub.
I whacked the top half of the agitator with the socket wrench to drive it upward and separate it from the large bottom half. Pieces fell out, as expected. I spent a long time cleaning the inside of the agitator (it was nasty) and then reassembled everything according to the instructions. The instructions said to remove two tabs on the lower part of the agitator. I was nervous about it, but did it anyway and it seemd to have no adverse affect. I got some lithium grease out of my grease gun and lubricated the plastic thrust washer as the instructions said. The kit didn't include the proper grease, which irritated me, but hopefully regular lithium grease will work okay.
Reassembly was easy once everything was aligned properly.
The part that came off did not have a retainer for the 4 ratchet dogs, but the repair kit did. This is crucial for reassembly.
I wouldn't hesitate to do this job again. Instructions were pretty good, for a change.