OK, solely in the interest of accuracy, what color is the master cylinder reservoir cap supposed to be? I have a silver one and a gold one. I seem to recall the gold one as being period correct. Thoughts?
Should be painted black. Evidence tends to show that the entire MC-Booster assembly was painted as a unit from the supplier.
https://www.deadnutson.com/1969-72-mustang-shelby-master-cylinder/:~:text=Installing%20a%20power%20brake%20master%20cylinder%20is,and%20avoid%20scratching%20up%20the%20shock%20tower.