I have a 1966 mustang 289 with a 4100 Autolite carburetor on a stock ford intake. Carburetor number is C5ZF-F. I cannot get the engine to idle smoothly. I am eliminating the ignition system since the distributor, points, condenser, cap, rotor and plugs are new. I tried a spare set of plug wires with no change. I also tried a spare coil with no change. I can find no vacuum leaks and have about 19" of vacuum. Is there something I could have done wrong on the carburetor rebuild causing a rough idle. Thanks for your assistance.