Ok,
Using the plastic wheels is out of the question. Not because the wheels are not round or because the tires do not fit well; the issue is simply that I cannot figure out a way to true tires on plastic wheels.
Taking the wheels out is a bad idea as it may enlarge the axle hole. Leaving them on, and trying to true using the Tire Razor truer is possibly just as bad – that truer is wrong in so many ways, I will save the “review” for later.
Anyhow, we can still race a Carrera based GT series but we would have to change the wheels; not what I had in mind.