I have RennTech 50-5000 (Apex) 35 mm lowering springs. Plan on installing them when I install my 19" wheels and tires 255/40 fr and 275/40 rr take offs from a W221. My Benz is a S420 WITHOUT any auto leveling suspension or added weight options in rear. Up front is light weight small V8 which I assume is the lightest engine in U.S. produced W140 models. Lighter than the larger 12 cyl and the straight 6 cyl engines as well as the larger V8. Stock shims are 13 mm front and 18mm rear. What shims should I go with? Same as stock, 13mm, 18mm, 23mm all away around. Please give your set up detail and feedback. Much appreciated.