Yeah, when PD have fixed the drivetrain they've not added the part to go with it.
As mentioned above, the tools do exist to make non-existent cars from scratch, and a few people have made test cars, however I don't have the skill set to do so, nor space left in the game to fit them.
Currently there is a 0% chance that SSR11 will be in the mod, now or in the future. Nobody is researching how the tracks work, never mind how to modify or even convert them. If a miracle happens I'll do everything I can to get it in, but it's not worth even wishing for unless you have a lot of reverse-engineering expertise and want to tackle it yourself.