Correct finishes for Chevelle brake components?
 

Trying to correct some detail items on my 1972 Chevelle, 3rd week of March Kansas build. 402 Big Block, auto, 12 bolt.

Rear brake drums - natural cast, or black?

Front brake calipers - natural cast, or black?

Master cylinder - natural cast, or black?

Thanks

Hard to make some of the parts look assembly line correct because it looked so bad. Seen a nos Chevelle rear housing on eBay a few years ago and it was half bare metal and the other half looked like it was painted by a guy on a pogo stick. So correct for the drums 1/2 black. Both of the others I’ve seen nos were a thin layer of black with the machined surfaces bare metal. Not all nos parts are like assembly line but also seen assembly line pics of black brake parts as well as pics of black master cylinders in vintage pics of new cars.