I'm curious as to whether he (1869-1960), the last undisputed head of the royal house of Bourbon-Two Sicilies (the titular King Ferdinando III, whose only son died young), ever expressed any opinion on the subject of his successor. His brother Carlo never reneged on the renunciation of rights for himself and his descendants; but after his death in 1949, his only surviving son (Prince Alfonso, Duke of Calabria, born in 1901) contested the said renunciation and eventually pressed his claim on the defunct throne.

Of course the next surviving brother (Prince Ranieri, Duke of Castro) born in 1883) contested his nephew's claim, insisting that the renunciation was to be upheld. As I understand, he handed over the responsibilities of headship to his own son Ferdinando (1926-2008) in 1966, two years after the death of Alfonso, when his own son (Prince Carlo, 1938-2015) inherited the disputed claim.

The 1977 edition of BURKE'S GUIDE TO THE ROYAL FAMILIES OF EUROPE (containing material current up through the end of 1976) posted photos of the then-two rival claimants (i.e. Carlo and Ferdinando), and ended the chapter on Bourbon-Two Sicilies with the death in 1960 of their great-uncle. The book was unable to name a clear successor, stating simply "Disputed (see above)."

My only question is whether the said great-uncle named any successor, before dying. How exactly did he interpret the house laws, in particular? Did he uphold the exclusion of his brother Carlo's line, on the basis of the validity of his renunciation of rights?

I find it eerie that the succession dispute in the royal house didn't even erupt until a full century after it got deposed (as is common knowledge, the kingdom of the Two Sicilies got annexed by the House of Savoy and incorporated into a larger united kingdom of Italy, itself eventually deposed).