Help Radio Identification

[sickboy_1456]

Hey guys, I just pulled this radio out of a 66 C20 that was mostly all original. I'm trying to determine if this in fact true to the year and truck or was it a replacement long ago?

I've searched many pictures and it seems like the radio's I find for the 1966 had different knobs. These knobs match the original A/C knobs that came in some of the 64-66 trucks, but never seen them on the truck radios. I have seen them on early Corvettes, but hopefully someone can help me out. Any feedback would be appreciated.