Under the category of leave well enough alone:

I decided to upgrade the suspension on my '94 e420 to the Sportline suspension. Used all stock sportline parts except for struts/shocks, I went with Bilstein instead of the stock Sachs. The upper mount on the new (Bilstein) strut is 12mm, whereas the stock strut is 14mm.

Has anyone run into this before? Should I just drill out the mounting holes on the strut?

Any help is appreciated. Thanks.

Greg