I think the reason Neri looked more like himself in III was that he didn't have much to do or say in the other two. The only scene in which he was the subject in II was deleted. He was a hell of boat skipper in II.
"Io sono stanco, sono imbigliato, and I wan't everyone here to know, there ain't gonna be no trouble from me..Don Corleone..Cicc' a port!"
"I stood in the courtroom like a fool."
"I am Constanza: Lord of the idiots."
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