Bilstein top nut how to tighten
 

I am installing bilsteins on my 380sl and after an hour of deep thought I cannot figure out to tighten the top nut with the teflon seal. There is no room no matter what I remove to get two wrenches on it. I was thinking of using an impact wrench but am not sure. The only other thought was to use vice grip to hold the top of the piston under the fender then tight the top nut. Anybody have any thoughts?

There is a Lisle tool that I used to do this, it didn't fit quite right, and part of the top of the shock broke inside of it, but it was only $10 or so.