Ok Guru of all things knowledgable on C5's your posting about the strange bracket, yes its 24v, but i have one for you, and even i carnt answer it..look at my chassis pics, and see where the chain tensioner spring is connected to, inside the square bracket box that holds the body shell, there is tiny lug for the spring, but in the OTHER side box, there is also another lug, diametrically opposed, with nothing to connect to it.
Maybe its a left hand drive/pedalled version..
so whats this lug for???