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The rear shocks are KW 3-way adjustable Motorsports units like the front. Spherical bearing equipped Battle Version rear links make everything adjustable and get rid of all the rubber. A Progress 3 way adjustable anti sway bar is used.
The rear lower control arm has been relocated within the limit of the rules to improve forward bite and to help with roll center location.
Drift Works rear knuckles lower the car while preserving wheel bump travel and keeping the geometry from getting out of hand, especially the roll center, even at a low ride height. Too low of a roll center on an S Chassis can make the car twitchy. 
The beauty of the S Chassis is that all of these parts are available off the shelf. Most of the parts for an S Chassis that is capable of winning FD can simply be bought and installed. That cannot be said of any other car.
Here is a close up look at the sturdy skidplate that protects the Winters quick change rear end. The Winters uses a spool differential for 100% lock and a sturdy 10.5″ ring gear. Typically the rear ratio is set to minimize shifts so gears 1-4 are used in the run up, then a single downshift is made during the run.
You can see how low the Winters hangs which is one of the drawbacks of the unit and why the skidplate is a nice touch. The Driveshaft Shop supplied the bulletproof 300M axles with Porsche 930 CV joints. 
