Here is the long answer. Both could be correct. Depending on plant,enviroment and spray equipment colors varied. Even today there is a great deal of variation on color. Look at all the variants for GM's 382E Pewter! When spraying the color you go over, number of coats, type of gun, fluid nozzle on gun, distance, air pressure, reduction ratio, reducer selection, type of paint (laquer, enamel, urethane, basecoat clearcoat or single stage)and paint manufacturer can all vary a color. If thats not enough golds and pewters can be the most difficult. A spectraphotometer (color camera) can help but it can still get weird. So to get started get some paint and do a spray out. ALWAYS START WITH A SPRAYOUT. and verify it to the car near the area you will be painting. If it doesn"t match take in a polished and flat part of the car at least 3"x3" and have a reading done then do another spray out. Some distributors even offer to tint colors for a fee. If you want what was "correct" for that car you should match it to an unmolested area and check around the car in case of repaint. Also make sure if the paint has sat that it gets shaken thoroughly as pigments settle.

Live to paint, paint to live!
Gene