When removing the axle take a pry bar and " snap " the end inside the tranny, to relsease it from the c-clip that holds it in.
In my experience i wouldn't replace the seal unless it's leaking , old and ratty looking or if you're afraid of tearing it up when taking the old one out.
If you are going to replace it , you can rent the seal driver from AZ and get it in there flush with the tranny. Remember , the seal must be driven from the outside, most ppl use a big socket like a 30 mm but that only sits on the inside of the seal. Also i put some gear oil on the outer edges of the seal just to make it slippery enough to slide it in.
And don't lose that spring that sits inside the seal.
Don't ask me how i know
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