I am going to pull those today, along with the fronts, to clean them. I have read they are magnetic and it would be safe to assume they have accumulated a lot of debris over the years.
Would the number of splines make a difference? The fact that the ECU is programmed with the R230 and not the R200? I figured this wouldn't be a problem since the light will only come on if I drive more than 5mph. Unless the sensors are programmed to read the spline input at that speed?
I finally got it back today from the body shop so I will hopefully figure it out.