14/04/2020 Edit: I made a slight modification to the part so it is now compatible with the front as well. The part can be mounted in the left rear or the front right, and you can mirror it in any slicer to have one for the other sides. Wheelbase is identical to the original. Ride height is adjustable by the leaf spring mounts like this: https://www.thingiverse.com/thing:2923284

Depending on your ride height you might need a longer steering arm to reach the servo. B14/24/36 arms work fine.

Original post: With this part you can mount the WPL leaf springs (from B series) to the rear of the C series. It gives a more authentic look but also makes the rear stiffer. It is suitable for heavier mods (big batteries), high loads or towing. I kept the original ride height and wheelbase as close as possible to the original (using the mount here: https://www.thingiverse.com/thing:2923284 )