It seems to me that maybe my car didn't have that problem when it was new, but developed it over time. My bulkheads all appear to be straight when I lay them on a flat surface, so maybe it's something with the chassis developing a curve over time? It always seems to tweak out fine once I tighten down the top deck with the car compressed at the shock towers. It's a shame nobody makes those chassis flattening plates for this car.