There isn't too much out there on DiFronzo. The coolest thing I ever read about him was in Cooley's When Corruption Was King.

Cooley wears a wire and goes into his auto dealership and gets him on tape saying that he didn't have to pay back any of the bookies he owed; if I remember correctly because he was instrumental in helping them, in his capacity as a corrupt lawyer, with several other things.

Cooley says he did that so that people didn't think he flipped just because he was deeply in debt to the mob bookies.

Of course, people say that anyway.