This was a big hassle for me too. I actually had to use a flat head, a hammer, and a pair of needle nose pliers. It worked best for me to put it on the end of the axle and using needle nose try to push one side on. After you get one half of it on you can use the flat head and hammer to gently knock the other side on and then down the splines into the groove. Easier said than done I know.
Fun fact: that’s the next thing I’m working on

It will not require removal of the bearing adjuster nuts or even the wheel. All you’ll need to do is remove the snap ring & hub flange!
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