Any 2 or 3 jaw puller should do the job. I bought a small/medium/large 3 jaw puller set from Harbor Freight and the medium one works just fine. I've removed the output flange (yolk) more than a few times. It can be a mofo sometimes. You might have to use a long breaker bar with the right size socket on the puller to get started.
Also, spray it with some PB blaster or liquid wrench. You might have some surface rust stopping you from getting started on the pull.
The output shaft is very sturdy and I doubt you can damage it unless you take apart the transmission and whack it with a sledge hammer. Never heard of anyone breaking one at the drag strip either. The input shaft is usually the first thing to break on a solid launch.
Last thing is for putting the flange back on. You can use the nut/metal washer to drive the flange back on but, DO NOT use the rubber washer. You will tear it up. After you drive the flange back on, remove the nut/metal washer. Then put the rubber washer in there and then the metal washer/nut and torque to specs.
If you have an impact wrench this is a one person job. If not you will need another set of hands and the right tool to hold the flange steady while you tighten the nut and drive the flange on. You can also use the impact the remove the flange if you have the right socket combination to hook up to the puller.