My '78 Camaro engine compartment was rusty and greasy, but otherwise everything was factory original. The Chevy's (and most GMs) had the same paint apps for the under hood items. Master cylinder, EGR base, hood hinges/latch, and fuel pump base were all cast iron in appearance. With the alternator, valve cover filter elbow, distributor base/hold-down, and wiper motor in cast aluminum. While the master cylinder lid, power brakes booster, EGR valve, alternator fan/pulley, and fuel pump top (bottom if it were on V8) were all gold anodized. The starter is flat black and the solenoid stainless steel. The Thermac air cleaner assembly is a gloss black. The fire wall and frame are flat black. Everything else that was painted, was semi-gloss black. The Mono-Jet carbs were gold colored zinc dichromate finish, except for the throttle body which was a silver
If you're asking about what was painted engine color on the engine, the factory basically assembled most of the engine together and then painted it all at once. Valve cover, timing cover, oil pan, water pump, balancer, intake manifold, and manual bell housing were all painted factory engine color with the block and head. The engine color before '78 was Chevy orange, while the '78 and '79 car 250s were GM blue (which was more of a robin's egg blue, but the modern spray can engine paint is actually Chrysler blue labeled GM blue). The distributor, fuel pump, starter, carb, pulleys, accessory brackets, exhaust manifold and EGR valve were bolted on after the engine was painted.
What it looked like when I bought it:
And current level of restoration:
