[Mr70]

I didn't know the frame was actually attached to it,so yes that makes sense.
I think that's a photo holder that was given out at auto shows.I've read Chevrolet traditionally had girls wandering their show exhibits,(or sometimes set up with a special prop like the Monza Jr Go-Kart say in 1964),with Polaroid cameras taking pix of visitors.Then they'd give them the pic in one of these folders.
They also did the same thing at the National Sales Convention and took pix of the dealers, factory guys etc.
Neat little piece of autoshow/convention history!