Cv8 diff advice

So I hade a cv8 2004 ls1 , there Is a small leak from one side of the diff where the drive shaft goes into it , I know they do wear and have issues , I hope .. but a simple fix is to charge the oil seal , is it more than one seal , and I think the part the end of drive shaft that joins to the diff can be pried out , is that the case ? And can some one advise the correct kit on Rock auto ? The bit I thought it maybe was out of stock part number USA 30285 , the full rebuild kit for the diff if it has the parts in it that I need ?? , appears to be r80rmk , not done this before plus not sure on part names , and is it do able on a drive way
Thanks in advance

Cheers , Message sent