I'm pretty sure I read somewhere that GK6 WAS supposed to be included in the painted grille group...I don't have anything in proof from Chrysler, just what has been printed in some of the rags back in the day from what they "heard"...did a google search on GK6 and found this...8/20/70: When a Cuda is order with one of the following paint codes the grill will be body color. [EB5], [FC7], [FE5], [GF7], [FJ6], [GK6], [EV2], [GW3], and [GY3].