Start with the basics:
New plugs are good....gapped correctly?
Points or electronic ignition?
What is the age and condition of the distributor cap and rotor?
Same goes for the spark plug wires.
What is the idle speed set at?
Is your electric choke fully open after about a minute?
How much old fuel in the tank and was it treated when you winterized?
Is timing correct?
Has the carb ever been rebuilt? Is it a 4160 or a 4010?
Once you get through that, I would look for a vacuum leak. Spray carb cleaner around the base of the carb with the engine running (use caution here as it's flammable). If your engine speeds up with the carb cleaner, you found your leak.
That should keep you busy for a while
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