Engine compartment detailing

I agree that engine compartment should match the car, I will see if it feesable to do. The car is a metalic silver, should the engine compartment be metallic? Should the entire engine compartment be silver, firewall fenderwells, radiator support, what about the cross members? Since I have no idea what the exact color of the car is, how do I get a similar color mixed? I have a compressor and sprayer so thats not a problem. What about wires and steering box etc. Thanks again for all the great answers