The 1984 and 1985 Dealer Brochures "equipment" list states that there is a Cargo Area Light that is "Std" on the ZX Turbo, the
ZX and the ZX 2+2. My 1985 ZX 2 seater (n/a) and a 1984 ZX Turbo member do not have this rear light feature. Steve Berman lists the lens for this light but shows that they're ONLY for 1979-1983 2+2 and 1984-1989 2+2's. These brochures are probably incorrect stating that the rear lights were on all models. I'm guessing that it was only available in the 2+2's so that the rear seat passengers had Z light.
Can anyone, 2+2 owners(?) confirm my suspicions?
I'm just trying to "Get the Facts Straight." (Dragnet) 
Thank you.
Update: The 2+2's had a cargo light that was mounted on/in the rear drivers side shock/speaker tower.