SEM color matching Help?

[dominer]

I have a 2004 Tahoe with gray interior. The main part of the interior is a lighter gray, SEM color that matched perfect is 15813 Medium Dark Pewter. DOes anybody know what the color would be for the darker gray?? I have this color on the dashboard and the trim ring that pops off from around the guage cluster, radio, Hvac controls etc. I having a hard time finding the right color for it. in the picture, the light gray (SEM color 15813 Med Dk Pewter) I need the top color which is darker. Has anyone purchased this color with sucess??Thanks for your help!!