I was taught by an old mechanic, (he had the "ear" to know exactly) on the engine side of your carb at the base of the carb is the fuel metering screw, turn it to the right until the engine slows and just starts to spit and sputter. Go back to the drivers side and increase the idle speed until you get to the 21 in. vacuum vicinity. you may have to adjust the distributor a little again to compensate for the lower fuel ratio. Continue this round robin until you come to an agreeable idle (don't forget to manually gun it from time to time to around 2000 to 2400 RPM to insure you are running good at all speeds) put it in gear from time to time to make sure it is doing what you want it to. When you are finally satisfied, lock everything down. Take it for a test drive, and fully expect that you may be fine tuning a few more times to come, then comes the onset of winter... you may have to fiddle a little bit more. I'ts an old car, show her some love! P.S.- A spray bottle of plain water sprayed in the carb at high RPM clears carbon.:love7: