GM codes generally start with WA, U, or L and are followed by four characters, like WA8624 or U8624. The code will either be on the parts ID sticker inside the door, (older cars will be near the bottom of the sticker, newer will be by the QR code in tiny text) in the glove compartment, or inside the spare wheel housing.
You can also find your car's color code by providing the last 8 digits of your VIN to the parts department of your local GM dealership and they will be able to tell you what the color is.
