Da Bull could be considered part of the "white collar" faction because of his many "legitimate" interests in construction, drywall, etc. But with 19 murders under his belt, he could hardly be considered "white collar" all the way.
DiCicco was a captain under Castellano. In one account I read, Gotti orginally wanted DiCicco to be the new Don, but Frankie sensed that Gotti ultimately wouldn't accept that as a permanent arrangement. He became consigliere after the Castellano hit.
DiCicco planned the hit, and it was a brilliant plan. Using six guys, identically dressed, wearing identical Astrakhan hats, and using identical .380 auto pistols, would make it awfully hard for a witness to make a positive ID of anyone.