Dean Meltzer is the name I was looking for: he built the body.
Like a lot of these specials, despite being named the Kopecky it might have been built for him rather that by him.
Anyway this is solved! Very good.
Apparently the car has a Maserati chassis and suspension from one of those that ran at Indianapolis in 1937, but has a Chrysler V8 bored out to 364 cu in. The car has survived and is currently undergoing restoration in California, retaining the configuration of this puzzle car.