no. it is not simple for a pre 1995 w140 S class. the back taillights are shaped differently on the Pre 95 W140's. A couple of members on BenzWorld have done the conversion on their 92, 93, and 94 W140's, and I believe that it costed them somewhere around $500-$600 at cheapest. It involves cutting and welding the back end, in order to get them to fit, or you could buy a new trunk lid, like harleyman did in this thread:
http://www.benzworld.org/forums/foru...241991&posts=3
I wish you best of luck in whatever you do, and I hope all of this information helps.[:)]
In regards to the Cleared turn signal lenses, I believe that you have to do the same thing as the rear taillights.