With reference to the constitution, how did Italian Fascism differ from National Socialism in Germany?

When Mussolini came to power in 1922, he did so in a profoundly different constitutional system than Hitler would encounter in 1933. The Kingdom of Italy had been on the winning side in the First World War and had thus retained its pre-war constitutional settlement untouched by the Paris Peace Accords, whereas Imperial Germany had been transformed by the Allied powers into an entirely new polity, the Weimar Republic. Italian Fascism was thus forced to make many compromises with existing forces of societal power, whereas National Socialism had a far freer hand from the start.First amongst these alternative sources of power within the Italian constitution was the monarchy. This had been abolished in Germany with the abdication of the Kaiser, but the House of Savoy remained in power in Italy and had a prominent and popular place in the running of the country. Mussolini's much-vaunted March on Rome was only permitted under royal sufference, with the army ready to crush it if necessary. The Italian military also swore their oath of allegiance to the King and not Il Duce, which proved a key distinction when the King ordered the military to join the Allied cause in 1943. The presence of a Head of State above Mussolini was a key difference between the Italian and German models. Secondly, the Catholic Church was a prominent source of societal power in Italy. Whereas Germany was split between a Protestant North and Catholic South, Italy was still a profoundly religious country and had many unresolved issues with the Papacy following the Risorgimento and the occupation of Rome in 1871. Mussolini was thus forced to come to a concordat with the Holy See during the Lateran Treaty of 1929, and allow the continuation of many Catholic projects, such as schools and youth groups, which challenged the Fascist societal model.