No.

Basically, grounding and grounded conductors not part of a multiconductor cable and smaller than 6 AWG are to have the proper insulation color and reidentification is not allowed. Under NEC 250.119 B the reidentification of the grounding conductor in a multiconductor cable is allowed only if "condition of maintenance and supervision insure that only qualified persons service the installation."

Conductors smaller than 6 AWG are available in the proper colors for use as grounding and grounded conductors, and reidentification for those purposes is not allowed.

- BOB