Just found this picture and thought I would share this information ....
It is a known fact that 1965 GTO's did not come from the factory with rear seat belts... BUT this car has them and they are blue and have been in there since day 1 of delivery.
I asked the original owner why does it have rear seat belts? He explained that he was in the navy when he ordered and bought this car and NO cars could go the Navy base without seat belts on ALL seats. When he ordered the car the Dealer got them from GM and installed them prior to delivery.

They look black.

They are blue identical to the fronts .... I will try to find a better picture of them