I can highly recommend Campbell Auto Restoration (CAR).
CAR works on all kinds of muscle cars including original Cobras and replicas as well. I have a Holley 650 with a mechanical choke on the 302 that I am running in my FIA. They were able to make some adjustments to solve an issue where the motor would almost stall during heavy braking and the cold idle speed was not set correctly. After the adjustments, the car starts and runs great if it's cold or hot and the almost stalling issue is gone. CAR is very through and they take the time to understand what the are issues with the car that you are experiencing and what your goals are for the car.
In your case, there may be other problems as well contributing to the drivability issues that you are experiencing and an overall look at the ignition and fuel delivery systems may be in order as well, prior to making any adjustments to the carburetor.
They are not inexpensive, but they are competent, professional and in my experience has been that you get what you pay for.
https://www.campbellautorestoration.com/index.html
- Tim