Some suggestions
Mike:
This is an interesting subject
First question: Are you trying to be "factory correct" or are you just interested in "cleaning her up"? If just cleaning her up (I call this the "DuPont approach") you can use whatever you think looks good. If you are going for a factory finish you might want to study your auto a bit more to determine the correct "sheen" for your year.
I am not certain about the 1960 year, but my 62 is getting this treatment as we speak. I have the front clip removed and disassembled, so that should make things a bit easier. The black under the hood has been referred to as both "semi-gloss" and "semi-flat" black.
Here's how I matched the color for my '62:
I have a buddy restoring a 1964 GTO and he has a very detailed book with all the colors and their codes linked. His is a factory correct car. His engine bay looks to be the same semi-XXXX black as my 1962. So I copied the paint code from his book, went down to the paint store and showed them what I had. Then we mixed a gallon of that color up (it had a lot of blue tint as I recall) in the same line of paint as I am painting the body (PPG single stage).
So we chose a gallon of PPG "Concept DCC", an acrylic urethane, two component product. We are using a reducer and a hardener. It's basically an exterior paint mixed to have that semi-flat/gloss black look. Cost was around $160 a gallon. I am not going for "factory perfect", just "really good driver", and I want this to wear well. Hence the 2K mixture with hardener. A bit more expensive than spray cans, but when you drool on it, your stomach acids won't wear off the semi-flat shine
I wanted the inside of the engine bay to hold up under tough conditions, like fluids and dropping wrenches, and so forth
Hope this helps. Sorry i don't have that code right near me or I would pass it along. I can get it, but it's 25 miles away.
I'm sure others will have equally good suggestions!
Best,
TomK