question for you resto experts

I have a 66 Barracuda that has been in my family since the early 70s. It is completely stock with 26K miles. The car sat at my dads for several years without being started or driven, so the fuel system, brakes, cooling and ignition system is in need of some TLC. I have the distributor out for rebuild, and it has engine paint over spray on it. I don't think my dad ever did any painting on the engine, so my question is, could this paint have happened at the factory? If so, should I leave it that way or clean it up and make it look nice? I want to keep it as original as I can and don't want to do anything that would effect the value of this survivor.