My '53 Jubilee manual says the main needle (the one with the knob at the end of the carb) is 1 1/4 turns out to begin, then under load turn it in til power drops off, then out til power picks up and runs smotth.
The idle needle goes in til seated (before starting) and out about 1 turn. Start the engine and adjust, in for rich and out for lean.
Set idle speed stop screw to 450 RPM. HTH