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@gfk_velo
35 x 24F is the old Italian thread (now largely redundant), you will find that an English threaded sprocket might just go on with a fight, but it'll be a very tight fit if it does & there is a fair chance of thread damage:
35 is the OD of the thread in mm
24F is the number of threads (filetto) per inch (yes, I know it's a crazy mix of units)
1.37 x 25.4 (mm in an inch) = 34.8 mm internal diameter on the sprocket, 35 mm outside diameter of the freewheel boss. That's an "interference" of 0.1 mm on the radius, about double what holds, say, a headset cup in place in the frame.
The threads per inch (TPI) match up, so no big problem there, except that Italian threads are ISO-form and are a subtly different shape to British Standard Cycle threads - you can usually get away with that aspect though.
Manufacturing tolerances and wear and tear on the hub thread might make the fit a bit looser but I wouldn't bet on it.
Better will be to cast around for an Italian threaded sprocket.