I ended up with a box of slides from a major Buick-Oldsmobile show previewing the 1977 Buick and Oldsmobile models. The show included Riveria and Toronado models that never saw the light of day. Also in the gallery are shots of Olds and Buick J-coupes that were never produced. The show probably took place in 1975. In the background on the above image above the deck lid to the left of the door is a Gray Counts rendering.
Click on any thumbnail to open the gallery of images.