To get all the gauge face colors to match you might want to resurface them with new decals, even the new gauges.
http://www.americanclassic.com/images/SP175.jpg

If your referring to the bezel color I used a krylon rattle can paint. Not an exact match but I painted the entire bezel
http://www.acehardwareoutlet.com/ProductDetails.aspx?SKU=17220

Here's Woodys tip on gauge restoration,   He offers dry transfers. 
http://www.pbase.com/czechman/instruments
Good luck