Just read 250.64(D) and I don't see a problem with doing it that way and what I noted is that the GEC "tap" conductors must extend inside the panels involved. So coming off the meter base don't solve the problem that Roger stated about parallel conductors. I'm still struggling with the fact that we are having a parallel situation here. I don't think it is a true parallel condition. We do have conductors that are both returning to the Xformer but the GEC is really just a back-up for the Neutral but even if we, for one fleeting moment, considered them in parallel the different sizes would violate 310.4. If the code considered them to be in parallel then I'd expect them to comply with 310.4.
