Chuck the Allied back in the water in Italy could be an idea? There would be enough troops if no Kursk.
If the Italian invasions are unsuccessful, surely Overlord will be re-looked?
If Manstein's elastic defense is carried to the limit instead of attacking at Kursk, leaving the Russians to attack, would the Russian losses be too significant for a continued offensive in 1943?
If so, that would not look for Overlord?
Ivan