Complex sentence: After Gotti took control of the Family, he removed Gallo as Consigliere and replaced him with Sammy (The Bull) Gravano, who later become the Underboss of the Family and a goverment informant.
Split into simpler sentences: After Gotti took control of the Family he removed Gallo as Consigliere and replaced him with Sammy (The Bull) Gravano. Gravano would later become the Underboss of the Family and a goverment informant.