blinguskahn
Super Freak
Looks like Tiger and Mark X use Hammerheads torso. It doesn't look like his head, legs or arms are used for any other armors. Not sure about Nightclub. Chest looks unique. But arms, legs and head???? Maybe someone else knows .
Look to me like everything on Nightclub is "unique".
Did some looking myself and added your observations...
Mk. VIII uses Nightclub head (debatable, most think Hot Rod/IP/WM Mk. II head).
Mk. X uses Hammerhead chest.
Mk. XII uses Nightclub head (debatable, most think Hot Rod/IP/WM Mk. II head).
Mk. XIX "Tiger" uses Hammerhead chest.
Mk. XXIX "Fidler" uses Nightclub forearm (1).
Mk. XXXII "Romeo" uses Nightclub forearms and head.
Looks like everything else uses parts from armors HT already produced. I wonder if they'll make Nightclub or Hammerhead as the next unique armor. If you notice something wrong or omitted, please add to the list!