Yes on the exhaust, probably on the valve cover.
Some people seem to get away with paint on gasket surfaces. I haven't. Had to pull a 2.3 Ford turbo motor back apart because I painted the exhaust area on the head.
Chrysler big blocks have enough problems with valve cover leaks as it is, and the paint likely will make things worse.
Some carb cleaner or lacquer thinner should take the paint right off.
Jeff