All 1954-1955 Chevrolet/GMC trucks came from the factory with a blank-out plate to cover where the radio would be installed. As this accessory was dealer installed the plate could be removed (probably thrown away) and the new radio added.
This blank-out plate and its two special clips has become very rare in recent years. They are not being reproduced. The enclosed photos show an original painted plate. The Chevrolet unit is the interior cab pearl beige color with a stamped bow-tie in black. GMC chose to not add their logo. These plates are just like Chevrolet except have a smooth surface with no trade letters.
Back View (above)