Pretty easy to do from what you have. Take your first image with the gold wheels: 1. Polygon lasso tool and select the gold parts of the wheel 2. Copy and Paste (or Apple+J on mac) and you will have your selection in a new layer 3. Image - Adjust - Hue/Saturation: Turn the saturation down, gold will look black and white 4. Image - Adjust - Levels: Drag in the white and grey to the left. Black some the other way to compensate for washing out
Step 4 could also probably be accomplished with Brightness/Contrast.