'69-'74 Stingray 5 speed. Same as the standard Stingray except the 5 speed guards had the elongated rear tab to clear the geat casset. The standard has a short rear tab like the other guard you show. I know I responded you on the other site but good to have the info here as well.
I STRIP THE PAIN OFF ITS CHROM
Or it might even be a stripped paint guard from a Krate / Fastback. If it's chrome underneath, it's from a Krate or Fastback. If its bare metal, it's from a 5 speed.
I see traces of chrome, under that silver spray bomb paint. My bet is that its originally from a Pea Picker Krate!!