Both Chevrolet and GMC used the same steering wheel during the 1947-1953 Advance Design years. To keep the two makes just a little different the horn buttons had a separate design. Thus, the driver was always given a close view of the name of the truck he was driving.
Chevrolet: Horn cap is chrome and then painted with steering wheel color. The raised Chevrolet letters and surrounding ridges are free of the paint so the chrome is visible (above)
Horn cap painted to match the steering wheel with red lettering. No chrome. (above)