What is length? IF 250.4(A)(5) can be satisfied mathematically, this may be something to consider.
As an inspector, I don't use 90.4 to waive specific requirements very often, but if the math shows that an undersized EGC is installed in a metallic raceway is better than a full sized EGC installed in say PVC, I would consider OK'ing the installation.
Can you give us the length so that I could crunch numbers?
