I own 2 1962 Ford Galaxies with 3X2 carb setup on a 406 engine. I have the same problem on both engines. One is a lot worse than the other. While the car is idling, it is extremely rich. I have had this problem on one of the cars for approximately 40 years. I have tried various things from people's suggestions, but none have been successful. I have changed the power valves from 6.0 to 2.0. They have Holley carburetors on them. Any suggestions will be appreciated.