I did find a good thread that discusses it in detail titled: 1965 289 engine black paint
Caspian65 recommended:
Here's a good formula to spray with a gun.
PPG DCC9300, black with SU4985 universal matting agent. Use 3:3:0.5:1 (Paint:Flattener:Reducer:Hardener
Prime the bare metal with PPG DP90LF epoxy primer. Be sure to topcoat within 48 hours for a chemical bond.
You may want to spray out on a test panel and let it dry. I've had to adjust the flattener down a bit, like 2.75 if it dries too dull. Also, don't freak out if the paint looks too glossy right after painting. Wait a few hours and it should dry in perfect.
For engine bays, I like to use a 3:2.5 ratio with 2 passes, 1.4 tip hvlp gun.
This is a very durable paint system, you can use the same paint on many other areas, just flatten accordingly. It takes extra work and equipment, but you'll be very happy with the results. I use DCC paint for interiors also, looks great when done right.