I've done some research.

SLS wagon rear shocks have a 2 bolt lower mount and the sedan has one. Both have a stem on the upper. It looks like the lower control arm is different in the lower shock mounting area but converting this to a single bolt won't be difficult.

While I'm capable of fixing every system on a car, there comes a point of not being worth it to spend big $$ for no real gain. Especially when I have a 97 E320 sedan parts car sitting here.

I'm going to try to look at the car sometime this weekend.