I did this recently on my w124 here:

W124 Strut mounts and boots

As the other poster added, if your struts are NOT relatively new, then it is easy. If your struts are new, you'll need extra helpings of spinach to compress the strut in this position.

I changed the mounts but soon after changed the struts also. I should have just done them together. There were no obvious signs of strut failure but comparing them to new ones, it was clear they were worn out being original to the car with 135m.

glenmore
1991 300CE
2000 C280
1990 LS400