I don't really see the problem. Running the sense array is so much faster than a car moves, that you can happily read all sensors first, put the measurement results in an array, and after that start figuring out which LEDs you want to light up at what brightness and colour and whatnot.
For resistors (and caps) you can get sets of 20 pcs of 30 different values. Cheap, and very convenient to have at hand. Indeed you never really know what you need beforehand.
Heres the literal first attempt after receiving everything after a delay in shipping.
Its a basic setup that reads the sensor and gives an Trigger to the LED whenever something is <= 10cm.
Now onward to the next step, using 1+ Sensors and the adressable RGB-Strip.
