Fronts too, are a very easy DIY job. Get a jackstand if you don't already have one and use it to support the A-arm so that you don't have to compress the spring.
Remove tire. Jack up the car high enough to place jackstand underneath A-arm. Let car down some to support the A-arm. Two bolts hold the strut on down below, one 22 mm bolt holds it up top in the engine bay above the wheel well (you'll need a hex key [8mm?] to hold the strut arm while you loosen the 22mm bolt). Turn wheel to either side to gain better access to lower strut bolts.
Remember to replace the strut mounts (in bay), strut bump stops (rubber pieces that fit on strut arm -- original one will be red and really worn), and the strut bellows (accordion protective covers).
Use the car's weight with the jackstand to your advantage. Go slowly and carefully -- probably a 3 hour job for the first time DIY'er. Feel free to email if you have any Q's.
'91 300E, 212K miles