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The back of the car's unibody is cut away to the limits of Formula Drift's rules. The car is at SPD Motorsports getting some crash damage repaired before the next round. SPD's Scott Dodgion is one of the best crew chiefs in Formula Drift and there is no one more capable for helping develop a car. 
Compared to a lot of modern multilink Japanese suspension designs whose geometries can often be nightmares, the stock MX-5 geometry is relatively straightforward. Typically Japanese multi links have way too much rear anti for drift cars which hampers forward bite and reduces on throttle traction in general. Typically Japanese rear suspensions have too much toe steer as well. The Radbul's rear suspension geometry remains stock and no change is really needed. We do feel that the rear roll center is low due to the car being lowered and the roll axis is backward sloping. 
Like the front, KW 3-Way Motorsports rear dampers are used. The adjustable links are by Megan Racing and happen to be a nice blue to match the Wisefab front suspension.
The upper shock mount swivels on pillow ball bearings. The rebound adjuster is easily and quickly accessible. 
A Winters quick change differential is used with a spool differential. Quick change rear ends are quite popular in drifting as they are very strong and gearing can be finely adjusted to limit the amount of shifts needed on the course. The axles are Driveshaft shop super strong 300M parts with heavy duty 930 CV's. You can see the remote reservoirs for the KW Shocks mounted above the diff in this picture as well.
The rear brakes are two Willwood Dynapro 4 piston calipers, one for the foot pedal and another for the ASD handbrake lever. The two piece rotors are alloy Willwood hats with solid drilled Wilwood Ultralite sprint car rotors to keep unsprung weight down. The rear wheels are a 18×10.5 3 piece Rotiform SLC with a Nitto NT05 tire in 265/35-18. The latest compound Nittos provide tons of grip and are currently one of the best drifting tires in Formula D.
