hi,

I couldn't understand exactly what you're asking for, but first is it 2007 or newer? 2007 on it's an awesome car with minimal problems so far...

Renntech packages on a 500 series (CL/SL/S etc)? most possible Renntech options are visual/exterior styling add ons, unfortunately, except the supercharger option, none of the Renntech packages for the 5L V8 is worth spending a penny on, and for the price of the SC, you could easily pay that for difference between the CL500 & CL600 (which, btw, is an incredible engine, V12, biturbos!, underrated at 500HP; easily puts out 540-550 HP in real life :)