certi-card

I don't think any of the holders were riveted from the factory. The certicard holder was one piece that folded onto itself it had clips molded on it that pushed through pre-drilled holes in the inner fenderwells. in 68 it came out of the engine compartment and went in the glove box in a plastic sleeve with the owners manual.

here is a repop holder but factory one looks exactly like this.
http://www.megapartsusa.com/proddetail.asp?prod=124-GCH10

here is a good info link about them.
http://www.mmcdetroit.com/Certicards/