Nothing else but the shocks need come out of the car when you do the rear shocks. So really, there's nothing else you should do "while you're in there."
However, if he's never done the shocks before he should make sure he gets all the bushings and a new bump stop for each shock cause they can rot after such a length of time. You can get all that stuff on eeuroparts.
However, if he's never done the shocks before he should make sure he gets all the bushings and a new bump stop for each shock cause they can rot after such a length of time. You can get all that stuff on eeuroparts.