The Stovebolt Site Forums The Shop Area Interiors Gauge face colors on '51 GMC

Have you checked the ID plate for the correct year? The paperwork that you have may have been for another truck that you grandfather had. By chance, was your truck from Canada? They may have used a different color set of gauges.

This is what you can get from JIM CARTER'S I believe the transition year was late 1951, so the gauges for your truck may be the same ones that are used in the 1952 GMC.