Please be VERY careful when you change the transaxle output seals. Lots and lots of people, even experienced mechanics, screw this job up. The best way is to remove the transaxle and bell housing as the seal nuts set diff bearing pre-load and ring and pinion backlash.
If you insist on doing it in situ, then do one side at a time and make sure the seal nut goes back to EXACTLY the same position. If your diff is whining afterwards, you screwed up.