The only 2 factory tail options on a normally aspirated car from '75 to '84 were the fiberglass whale pictured here
1 piece, f/g ,w/ separate p/u lip, single grill
and the variant pictured here w/ the separate grill for the Ac condenser
1 piece, f/g, w/ p/u lip and 2 grills, standard on 930s from '75 -'77
and the poly-urethane one pictured here
2 piece, bolts on to a standard steel deck lid.
This is a "tea tray" type used on '78 - '89 930s
2 piece ,plastic ,w/ p/u lip that bolts on to a standard steel deck lid, never a factory n/a option but lots of owners did install them. The standard spoiler on all 930s '78 -89