Here is a picture of the X-215, turbo powered, topless, concept car that they showed in the Detroit Car Show in 1962. Read more about this car in Jim Noel’s bio.
This is the J-TR – a 1963 Concept Car. It too was built on a convertible platform. Note the exhaust port built into the rocker panel and the impressive interior. No side chrome! Great tail lights!
Pictures used with permission from: General Motors LLC