Here the Hi-Tech grilles and Details West dynamic brake box are shown in detail. I just guess-timated on the width I should add to the dynamic box. I added 0.040" but in retrospect probably should have added 0.060" instead. I added some styrene strip above the grilles to bring the dynamic box up a little higher. I have no idea how much it should go up, but this looks about right compared to the photos I've seen.