Lucky,

I have never replaced the rear sway bar in a wagon, but I have in a sedan. It is a little involved depending on the equipment you have to work with.

I have done it with the use of a two post lift and a transmission jack and I have also done it with nothing to use except a floor jack and jackstands. I'm sure it is not necessary to tell you which was easiest.

Either way, what you have to do is raise and support the car safely so that rear wheels can be removed and the body is supported. You put your jack under the rear suspension system and remove the subframe to body mount bolts, then lower the entire rear suspension enough that you can snake the bar through. The sway bar links and sway bar mounts should be removed before removing the subframe bolts.

On the wagon, it might be that the rear struts must be disconnected at the top, but I'm not sure.

Stiffening up the rear sway bar without other changes is sort of a personal preference thing. I've stiffened the rear bar only on several cars over the years and really like the result. It will take out a lot of the understeer.

On my 300E, I first put on Sportline bars front and rear, then I put the stock bar back on the front, then I put a 500E bar on the rear. That's when I really enjoyed the feel of the car. If I was starting over, I would put the 500E bar on the rear and be done with it. That's just my own personal preference. Yours and others may very well be different.

Good luck,